---
title: 'How Big Is a 4×6 Photo in Centimeters? A 6-Inch Print Is 10.16 × 15.24 cm: A Complete Photo Size Guide with A6 and 5×7 Comparisons'
url: https://joelin.cc/en/p/9035
source: https://joelin.cc/en/p/9035
lang: en
pubDate: '2026-10-12'
date_modified: '2026-10-12'
description: A 4×6 photo measures 10.16 × 15.24 cm—the print Taiwan calls a 6-inch photo. Compare A6 and 5×7 sizes, check 300 dpi pixel requirements, and understand cropping.
author: joe
ai_role: ai_only
translation_of: /p/9035
mentions:
  - name: Chunghwa Post
    sameAs:
      - https://www.wikidata.org/wiki/Q709259
---

# How Big Is a 4×6 Photo in Centimeters? A 6-Inch Print Is 10.16 × 15.24 cm: A Complete Photo Size Guide with A6 and 5×7 Comparisons

The original Chinese article was published on May 7, 2026, and last updated on September 30, 2026. The specifications, prices, and research below reflect that historical snapshot.

4×6, also written as 4\*6 or 4×6 寸, is an international standard photo print size measuring 10.16 × 15.24 cm, equivalent to 4 × 6 inches—which is where its name comes from. Photo-printing shops in Taiwan call it a “6-inch photo,” written as 6吋照片 or 六寸照; both refer to the same print. It is close to A6 paper (10.5 × 14.8 cm), but not identical: approximately 4 mm narrower and 4 mm longer.

![](https://image.joelin.cc/cdn-cgi/imagedelivery/0xu8EsaSar9n3zUKY5d7xw/migrations/wp/2026/05/4-6-%E6%98%AF%E5%A4%9A%E5%B0%91%E5%85%AC%E5%88%86-/hero)

I put this guide together because, over my years working in printing, the questions I hear most often are “What exactly is the difference between 4×6 and A6?”, “Can I mail a 4×6 photo as a postcard?”, and “Which size should I select to print a 4×6 on ibon?” Most answers online give only the numbers, without clearing up the confusion between standards or explaining the practical details. This article brings those pieces together.

## Complete 4×6 Size Conversion Table

The table below gives the dimensions of a 4×6 in different units for quick reference when ordering photo prints, printing, or designing:

| Unit | 4×6 dimensions |
| --- | --- |
| Centimeters (cm) | 10.16 × 15.24 |
| Millimeters (mm) | 102 × 152 (exactly 101.6 × 152.4) |
| Inches | 4 × 6 |
| Common Chinese name | 6 寸照片, or “6-inch photo,” as traditionally used by Taiwan's photo-printing industry |
| Pixels at 300 dpi (photo printing) | 1,200 × 1,800 |
| Pixels at 150 dpi (general output) | 600 × 900 |
| Pixels at 72 dpi (screen) | 288 × 432 |

Aspect ratio: 2:3, the most widely used ratio in the photo-printing industry.

Why it is called “4×6”:

The name comes directly from its dimensions: 4 inches × 6 inches. Taiwan's photo-printing industry usually calls it a “6 寸 photo,” naming it after the long edge. However, the traditional unit 寸 (cun) is actually 3.03 cm, so 6 cun would be 18.18 cm. “6 寸 photo” is therefore a customary name, rather than a strict conversion into traditional Chinese units. When you hear “6 寸 photo,” simply understand it as the 4×6 print size.

## Comparing 4×6, A6, and 5×7: The Sizes Most Often Confused

Many people confuse 4×6 with A6, but they come from completely different standards systems:

| Size | Centimeters | Standards system | Main uses |
| --- | --- | --- | --- |
| 4×6 | 10.16 × 15.24 | US/imperial photo print standard | Photo prints |
| A6 | 10.5 × 14.8 | ISO 216 international paper standard | Paper, postcards, cards |
| 5×7 | 12.7 × 17.78 | US/imperial photo print standard | Enlarged photos, frames |
| 6×8 | 15.24 × 20.32 | US/imperial photo print standard | Wedding portraits, enlargements |

### How Many Millimeters Apart Are 4×6 and A6?

- A 4×6 is 10.16 cm wide and 15.24 cm tall, with a 2:3 aspect ratio.
- A6 is 10.5 cm wide and 14.8 cm tall, with an aspect ratio of 1:√2 ≈ 1:1.414.
- A 4×6 is approximately 4 mm narrower and 4 mm longer than A6.

In a side-by-side comparison, the biggest difference is the aspect ratio: 4×6 has a slender 2:3 shape, while A6's 1:√2 shape is somewhat squarer. Put an A6 sheet beside a 4×6 photo and you will clearly see that A6 looks “wider,” while the 4×6 looks “taller and slimmer.”

→ For a complete explanation of A6 paper itself, see the [Complete Guide to A6 Paper](/p/9020).

### Are 6×4 and 4×6 the Same?

Yes; only the orientation differs. A 6×4 is landscape, while a 4×6 is portrait. Their actual dimensions are identical—10.16 × 15.24 cm—and only the direction changes. All 4×6 printers support both orientations.

## Common Photo Sizes: 3×5 Through 8×10 in One Table

People searching for “photo sizes” often need more than just 4×6. Here are the common sizes used in Taiwan's photo-printing system, including the local “inch” names, which refer to the length of the long edge in inches:

| Size | Common name | Centimeters (cm) | Pixels for 300 DPI printing | Complete guide |
| --- | --- | --- | --- | --- |
| 3×5 | Three-by-five / 3R | 8.9 × 12.7 | 1,050 × 1,500 | [3×5 Size Guide](/p/9788) (actually 3.5×5, equivalent to Japan's L判) |
| 4×6 | 6-inch photo / 六寸照 | 10.16 × 15.24 | 1,200 × 1,800 | ✅ This page |
| 5×7 | 7-inch photo / 七寸照 | 12.7 × 17.78 | 1,500 × 2,100 | [5×7 Size Guide](/p/9103) |
| 6×8 | 8-inch photo / 八寸照 | 15.24 × 20.32 | 1,800 × 2,400 | [6×8 Size Guide](/p/9469) (exactly the area of two 4×6 prints) |
| 8×10 | 10-inch photo / 十寸照 | 20.32 × 25.4 | 2,400 × 3,000 | [8×10 Size Guide](/p/9610) |

Three quick rules: choose 4×6 for everyday photo printing, the main size at convenience stores and photo-printing shops; choose 5×7 or 6×8 for framed gifts, with frame-selection advice in [How to Choose a Photo Frame Size](/p/9457); and remember that ID photos are outside this table—they use the 1-inch/2-inch system, covered in the [ID Photo Size Overview](/p/9453).

How A5/A6 paper sizes relate to photo sizes: A5 is almost the same size as 6×8 ([A5 Size Guide](/p/9447)), while A6 is a little wider and shorter than 4×6, giving it a squarer shape. The reason is explained below in “Why 4×6?”

## What Gets Cropped When You Print a Phone Photo as a 4×6?

This is the most common unpleasant surprise in photo printing: phone photos have a 4:3 aspect ratio, but 4×6 photo paper is 3:2. Since the two differ, you have to make a choice:

- Full bleed (cropping): the photo is enlarged to fill the entire sheet, cropping approximately 11% of the image—the mathematical result of converting 4:3 to 3:2. The crop removes both ends along the long-edge direction: the top and bottom of portrait shots, or the left and right of landscape shots. Portraits with people near the edges or heads close to the frame are especially vulnerable.
- White borders (preserve the whole image): the entire image is printed, but white borders remain on two sides of the paper. Nothing in the image is lost; the trade-off is that it looks as though you have added a white frame.

My practical recommendations:

1. Keep people farther from the edges when shooting. Leave room for cropping as you compose, so the photo remains safe whichever way you print it.
2. Crop important photos yourself before submitting them. Use your phone's built-in editor to select a 3:2 or 2:3 ratio and crop manually. You decide which part to remove, rather than leaving it to the machine.
3. Kiosk terminology varies: full bleed/borderless/crop versus white margins/full image/borders. Checking the preview before printing is the safest approach.

Also remember that photos sent through LINE are compressed. Always use the original files for printing. For a complete comparison of pixel requirements across print sizes and DPI settings, see [How Many Pixels Is 300 DPI? Complete Reference Table](/p/9086).

## Why 4×6? The Origins of Photo Sizes

After finding the dimensions in centimeters, many people have another question: who decided on these numbers? The answer is more interesting than you might expect. Photo sizes were not chosen arbitrarily; they were determined by film and machines.

### The Two Ancestors of 4×6: 35 mm Film and Postcards

The first source is film. A 35 mm film frame measures 24 × 36 mm, giving it an aspect ratio of exactly 3:2. This format has been used since the 1920s and forms the foundation of consumer photography. Enlarge a 3:2 image until its short edge measures 4 inches, and the long edge becomes exactly 6 inches. That is where 4×6 comes from: its dimensions follow from the film's aspect ratio, rather than being designed independently.

The second source is postcards. A 4×6-inch print is also very close to the traditional postcard size, allowing printed photos to fit directly into existing albums, frames, and postcard racks without requiring a separate format. Together, those two conditions made 4×6 the global default for photo printing.

(This shared history is also why people still often ask about “postcard size” and “4×6 photo size” as though they were the same thing. For the full specifications from a postcard perspective, see the [Complete Guide to Postcard Sizes](/p/6196).)

### Why Do Photos Use Inches While Paper Uses Centimeters? They Are Two Different Systems

This is the fundamental reason the dimensions never quite line up:

| | Photo-size system | Paper-size system |
| --- | --- | --- |
| Examples | 4×6, 5×7, 6×8, 8×10 | A4, A5, A6, B6 |
| Origins | British and American photographic industry, dating to the Kodak era | German DIN → international ISO 216 |
| Units | Inches | Millimeters |
| Aspect ratio | Different for each size; 4×6 is 3:2 | √2, approximately 1:1.414, for every size |
| Design logic | Accommodates film frame formats | Preserves the aspect ratio when folded in half; A0 has an area of 1 square meter |

That is why A6 (10.5 × 14.8 cm) and 4×6 (10.16 × 15.24 cm) always differ slightly. Their aspect ratios are fundamentally different—1.409 versus 1.500. It is not a matter of imprecise manufacturing; the two systems have different origins. To understand the full logic of the A series, see the [Complete A6 Size Guide](/p/9020). The B series adds another complication: separate ISO and JIS standards, explained in the [B6 Size Guide](/p/9475).

### Each R-Series Size Has a Different Aspect Ratio; the A Series Always Has One

The easiest cell to misread in the table above is “Aspect ratio.” The photo side is often described as “photos are 3:2,” but only 4×6 is 3:2. Every other size has its own ratio:

| Size | Inches | Long-edge-to-short-edge ratio | Image format it matches exactly |
| --- | --- | --- | --- |
| 3×5 (3R / L判) | 3.5 × 5 | 1.43 | None |
| 4×6 (4R) | 4 × 6 | 1.50 | The 3:2 format of 35 mm film and SLR cameras |
| 5×7 (5R) | 5 × 7 | 1.40 | None |
| 6×8 (6R) | 6 × 8 | 1.33 | The 4:3 format of phones and consumer digital cameras |
| 8×10 (8R) | 8 × 10 | 1.25 | Instagram's 4:5 portrait format |
| All A-series sizes | — | 1.414 | None; the ratio comes from mathematics, rather than cameras |

This happens because the two systems follow different rules for generating sizes. The A series fixes the aspect ratio at √2, then produces each smaller size by folding in half, so its nine sizes share one shape. In the R series, the short edge follows the R number, while the long edge retains the traditional length of each individual size. Nobody standardized their aspect ratios, so the shapes become closer to square as the R number increases.

This has direct consequences for printing, because the amount cropped depends on how far your image's aspect ratio differs from the paper's:

- A 4:3 phone photo needs no cropping on 6×8 paper, loses about 5% on 5×7, and loses about 11% on 4×6.
- A 3:2 image shot with an SLR or a camera mode needs no cropping on 4×6 paper, loses about 7% on 5×7, and loses about 17% on 8×10.
- If you want an enlargement without recomposing the image, first check whether your photo is 4:3 or 3:2, then choose the print size with the closest ratio. That is more useful than simply choosing “something bigger.”

### Why Is 6×8 Exactly the Area of Two 4×6 Prints? They Come from the Same Paper Roll

This is not a coincidence; it is determined by the machine.

Professional photo printers used in photo-printing shops and at events—dye-sublimation models—use rolls of photo paper that are 6 inches wide. With the paper width fixed at 6 inches, the machine can only choose how long a piece to cut:

- Cut at 4 inches → 4×6
- Cut at 8 inches → 6×8
- Cut at 9 inches → 6×9

The same paper roll, the same machine, just a different cut length. That is why a 6×8 has exactly the area of two 4×6 prints ([6×8 Size Guide](/p/9469)). A 5×7, however, requires a different paper roll, which is also why some shops take a little longer or charge a little more for that size.

This also answers a common question: in Taiwan's terms 六寸照 (“6-inch photo”) and 八寸照 (“8-inch photo”), “寸” refers to the long edge in inches. A 4×6 has a 6-inch long edge, hence 六寸照; a 6×8 has an 8-inch long edge, hence 八寸照. It does not refer to area or the Taiwanese unit cun. Written with Arabic numerals, the same terms become 6吋 and 8吋. Searches for “6吋 in centimeters” and “六寸 in centimeters” are asking for the same answer.

### Why Can't You Change the Sizes of Instant Photos and Photo-Booth Prints?

Because their dimensions are determined by the film's structure, rather than simply by the paper.

An instant-photo card contains more than photographic paper: it also holds a pod of developing chemicals and a complete set of chemical layers. The dimensions are locked in by the chemical pod and roller mechanism. To change them, a manufacturer would need to rebuild the entire production line. That is why instant-photo formats have barely changed in decades. See the [Instant Photo Size Guide](/p/9095) for the differences between formats.

Photo booths follow a different logic: their built-in printers determine the paper width, while software determines how many images fit into the layout. The size of a single printed sheet is therefore fixed, but the number of images and their arrangement can change. See [Photo-Booth Print Sizes](/p/4008) and [Four-Cut Photo Print Sizes](/p/4126).

### A One-Sentence Summary for Each Size

| Size | What determines it |
| --- | --- |
| 4×6 | The 3:2 ratio of 35 mm film, plus the existing postcard ecosystem |
| 5×7 / 8×10 | The short edge follows the R number, while the long edge retains its traditional length, resulting in different aspect ratios |
| 6×8, 6×9 | The paper roll's 6-inch width; only the cut length differs |
| A4 / A5 / A6 | ISO 216's mathematical √2 design, unrelated to photography |
| Instant photos | The film's chemical-pod structure, which cannot readily be changed |

Knowing these origins has a practical benefit: you can tell which sizes can be converted into each other and which cannot. Sizes produced from the same roll, such as 4×6 ↔ 6×8, are the simplest to convert, although their different ratios still require cropping. Moving between systems, such as 4×6 ↔ A6, requires recomposing the image. For instant photos and photo-booth prints, do not expect to change the format.

## Printing 4×6 Photos at Convenience Stores: ibon, 7-Eleven, and FamilyMart

The 4×6 printing services offered by Taiwan's four major convenience-store chains all use the same dimensions:

| Channel | Price per 4×6 print | Equipment |
| --- | --- | --- |
| 7-Eleven (ibon) | NT$5–10 | Uses the same 4×6 format as photo booths |
| FamilyMart (FamiPort) | NT$5–10 | Same as above |
| Hi-Life (Life-ET) | NT$5–10 | Same as above |
| OK Mart | NT$5–10 | Same as above |

Details to watch when printing:

- White borders: convenience-store printers leave white margins by default. If you do not want them, design the photo to extend all the way to the image edges, including bleed. → [How to Avoid White Borders on ibon Postcards](/p/4235)
- File specifications: prepare a JPG measuring 1,200 × 1,800 pixels at 300 dpi.
- Portrait or landscape: convenience-store printers automatically rotate files to align with the long edge, but I recommend rotating the image yourself before uploading it.

→ For a complete tutorial on printing postcards at convenience stores, see [ibon Postcard Sizes / 7-Eleven Postcard Sizes Explained](/p/4307).

## Where Should You Print 4×6 Photos? Calculate the Total Cost of This Order First

After checking the dimensions, the next question is usually where to print photos—commonly called 晒相 in Hong Kong—and how to get the best value. There is one rule: compare the total cost including shipping, rather than the price per print. If you urgently need a few photos, use a convenience-store kiosk. You can print just one, pay no shipping, and take it away immediately. If you are printing several dozen family photos, use an online photo-printing service. Unit prices are much lower, but you must meet the minimum quantity and wait a few business days. If you can wait and are organizing a large batch, online printing at a Japanese factory with cross-border shipping to Taiwan can also be economical. However, delivery takes two to three weeks, so do not choose it for urgent prints.

Check three things before ordering to avoid paying for a second print run:

1. Review the cropping preview before submitting. When printing a 4:3 phone photo as a 4×6, you must choose between full bleed and white borders, as explained above in “What Gets Cropped When You Print a Phone Photo as a 4×6?” Online photo-printing apps provide previews after uploading, and convenience-store kiosks display them on screen.
2. Meet the minimum quantity before ordering. Online services have separate minimum quantities for each print size. If your order falls below the threshold, a convenience-store kiosk may be better value.
3. Distinguish photographic printing from inkjet printing. The same provider may offer both processes at different prices. Confirm which one you have selected before ordering.

I maintain a separate page covering print sizes, unit prices, minimum quantities, shipping fees, and example totals for online services, convenience-store kiosks, and cross-border printing from Japan. When prices change, only that page needs updating: [Taiwan Photo-Printing Channel Comparison](/p/9786).

## Japan's Default Photo Print Is Not 4×6

When you print photos at a convenience store or photo shop in Japan, the machine's default output is not 4×6. It is L判, measuring 8.9 × 12.7 cm—one size smaller than 4×6.

L判 is Japan's standard photo print size. Its name dates to the rapid spread of 35 mm film cameras in Japan during the 1960s and 1970s, when it was named for being larger than the then-common サービス判 (“service-size”) print. Almost all Japanese photo albums, frames, and printing machines use it as their baseline.

Here is how Japanese print-size names correspond to Taiwan's terminology:

| Japanese name | Centimeters | Equivalent in Taiwan |
| --- | --- | --- |
| L判 | 8.9 × 12.7 | [3×5 (3R)](/p/9788), now less common in Taiwan |
| KG判 | 10.2 × 15.2 | 4×6, or a 6-inch photo |
| 2L判 | 12.7 × 17.8 | 5×7, or a 7-inch photo |
| 六切 | 20.3 × 25.4 | 8×10, or a 10-inch photo |

The mismatch causes problems in both directions. Photos printed in Japan and brought back to Taiwan do not fit albums designed around 4×6, because L判's long edge is about 2.5 cm shorter. Conversely, if you buy a frame or album in Japan and bring it back to Taiwan, locally printed 4×6 photos will not fit; you have to trim the edges.

To print Taiwan's usual size in Japan, look for KG判 in the machine's menu. That is the equivalent of 4×6. I explain why L判 has remained in use in Japan for sixty years, and where you can still print this size in Taiwan, in [What Size Is a 3×5 Photo?](/p/9788).

## What Is 4×6 Used For? Six Common Uses

1. Photo prints: the largest use category. Home photo albums, wedding photos, and travel records all use 4×6.
2. Postcards: a 4×6's long edge exceeds Chunghwa Post's postcard limit, so domestic mailing may be charged at letter rates. Print on A6 if you want to send it as a postcard. → [Complete Postcard Size Guide](/p/6196)
3. Photo-booth prints: Korean-style photo booths and four-cut photos usually use the 4×6 format.
4. Desktop photo frames: one of the most common standard frame sizes.
5. Promotional materials: restaurant offer cards and event flyers often use 4×6.
6. Custom phone cases: 4×6 printing templates are common in phone-case factories.

## A Graduation-Season Note: Graduation-Gown ID Photo Sizes

Every graduation season, readers who have checked the dimensions on this page ask a follow-up question: what size should a graduation-gown photo submitted for a yearbook be? The short answer is that graduation-gown photos have no separate legally prescribed size. Printed copies use the 2-inch format, 3.5 × 4.5 cm; digital files must follow the school's announcement, commonly a 300 dpi JPG. The important distinction is the intended use: you cannot wear a graduation gown in national ID card or passport photos, while yearbooks usually require one. For the full rules, see [Graduation-Gown ID Photo Rules and Uses](/p/9365). If you are in Taipei and want to take one right away, [graduation-gown ID photos in Ximending](https://plab.one/p/1004/) can be taken at a self-service booth, with the digital files available immediately.

## 4×6 in English

4×6 is a standard photo print size used widely in the United States and internationally: 4 inches × 6 inches, which equals 10.16 × 15.24 cm (or roughly 102 × 152 mm). The aspect ratio is 2:3, the most common ratio for printed photographs.

4×6 differs from ISO 216 A6 paper (10.5 × 14.8 cm), which uses a 1:√2 ratio. They look similar in area but are not interchangeable for precision printing.

| Photo Size | Inches | Centimeters | Common use |
| --- | --- | --- | --- |
| 4×6 | 4 × 6 | 10.16 × 15.24 | Standard photo |
| 5×7 | 5 × 7 | 12.7 × 17.78 | Enlargement |
| 8×10 | 8 × 10 | 20.32 × 25.4 | Framed portrait |
| Wallet | 2.5 × 3.5 | 6.35 × 8.89 | Wallet-size photo |

## Frequently Asked Questions About 4×6

### How Many Inches Is a 4×6 Photo?

Taiwan's photo-printing industry commonly calls it a “6 寸 photo,” naming it after the long edge. Its actual dimensions, however, are 4 inches × 6 inches = 10.16 × 15.24 cm. This is not equivalent to 6 cun in the strict traditional Chinese unit system, where 6 cun = 18.18 cm. When you hear “6 寸 photo,” simply understand it as the 4×6 print size.

### Are 4×6 and A6 the Same Thing?

No. 4×6 is a photo print size (10.16 × 15.24 cm), while A6 is a paper size (10.5 × 14.8 cm). Their dimensions are close but different, as are their aspect ratios: 2:3 for 4×6 and 1:√2 for A6. For the detailed differences, see the [Complete Guide to A6 Paper](/p/9020).

### Can I Mail a 4×6 Photo as a Postcard?

For domestic mailing in Taiwan, take care: Chunghwa Post's operating regulations set a maximum postcard size of 14.8 × 10.5 cm, with a permitted tolerance of 2 mm. A 4×6 photo's 15.24 cm long edge exceeds that limit, so a self-printed 4×6 photo may be charged at letter rates. This was checked against Chunghwa Post's postcard specifications in September 2026. If you want postcard postage, printing on A6 (10.5 × 14.8 cm) is the safest choice. International mailing has separate specifications; follow the guidance at the post office counter. See [Postcard Sizes and Mailing Rules](/p/6196) for details.

### How Many Pixels Do I Need to Print a 4×6 Photo?

Prepare an image of at least 1,200 × 1,800 pixels, the standard for 300 dpi printing. Lower resolutions can look grainy in print. Phone-camera photos are usually 12 MP or more, far above this requirement.

For a complete table of pixel requirements, from 1-inch ID photos through A4, see [How Many Pixels Does a 4×6 Photo Need to Avoid Blurriness?](/p/9086).

### Are 4×6 and 4R the Same?

Yes. 4R is another name used in Asian photo printing, particularly in Japan and Hong Kong, for the US 4×6 size: 10.16 × 15.24 cm. When someone in Hong Kong says “4R 相,” they mean a 4×6 photo.

### How Much Does One 4×6 Print Cost, and Where Is the Best Value?

It depends on how many photos you print at once. Compare the total cost including shipping, rather than the unit price. For a few urgent prints, choose a convenience-store kiosk: you can print just one, pay no shipping, and take it away immediately. For several dozen family photos, choose online printing. Unit prices are much lower, but you must meet the minimum quantity and add shipping. For unit prices, minimum quantities, shipping fees, and example totals across channels, see the [Taiwan Photo-Printing Channel Comparison](/p/9786).

## Size and Specification Encyclopedia: Guide to the Complete Series

I have written separate guides for the common sizes, organized into three groups according to what you want to do:

### ① Photo Printing and Framing: Inch-Based Sizes Named After the Long Edge

| Size | Centimeters | Uses | Guide |
| --- | --- | --- | --- |
| 4×6 (6-inch photo) | 10.16 × 15.24 | Main size for everyday photo prints and convenience-store printing | ✅ This page |
| 5×7 (7-inch photo) | 12.7 × 17.78 | Framing, commemorative photos | [5×7 Size Guide](/p/9103) |
| 6×8 (8-inch photo) | 15.24 × 20.32 | Framing larger images; the area of two 4×6 prints | [6×8 Size Guide](/p/9469) |
| Frame opening dimensions | Vary by size | Check before buying a frame | [How to Choose a Photo Frame Size](/p/9457) |
| Instant photos | mini / wide / square | Instax, Polaroid | [Instant Photo Sizes](/p/9095) |
| Photo-printing channels | Five providers compared including shipping | Where to print, minimum quantities, total cost including shipping | [Taiwan Photo-Printing Channel Comparison](/p/9786) |

### ② Paper and Printing: ISO Metric Sizes

| Size | Centimeters | Uses | Guide |
| --- | --- | --- | --- |
| A6 | 10.5 × 14.8 | Maximum postcard size, small cards | [Complete Guide to A6 Paper](/p/9020) |
| A5 | 14.8 × 21.0 | Booklets, notes | [A5 Size Guide](/p/9447) |
| A4 | 21.0 × 29.7 | Copier paper, documents | [A4 Size Guide](/p/9607) |
| A3 | 29.7 × 42 | Posters, charts; the area of two A4 sheets | [A3 Size Guide](/p/9609) |
| B6 | 12.5 × 17.6 | Planners; watch for the separate ISO and JIS standards | [B6 Size Guide](/p/9475) |
| B5 | JIS 18.2 × 25.7 | A main notebook size | [B5 Size Guide](/p/9608) |
| Postcards | Maximum 14.8 × 10.5 | Mailing through the post office | [Common Postcard Sizes](/p/6196) |
| Traditional sheet divisions (開數) | Full sheet / quarter sheet / eighth sheet | Traditional printing-house sizes, which do not align with the A series | [Taiwan Paper Sheet-Division Reference](/p/9615) |
| A2 | 42 × 59.4 | Posters, charts | [A2 Size Guide](/p/9612) |
| A1 | 59.4 × 84.1 | Large posters | [A1 Size Guide](/p/9611) |
| A0 | 84.1 × 118.9 | Large-format printing; the starting point of the A series | [A0 Size Guide](/p/9614) |
| B4 | JIS 25.7 × 36.4 | Exam papers; the area of two B5 sheets | [B4 Size Guide](/p/9613) |

### ③ ID Photos, Cards, and Printing Specifications

| Item | Specification | Guide |
| --- | --- | --- |
| 1-inch / 2-inch ID photos | 2.8 × 3.5 / 3.5 × 4.5 cm | [ID Photo Size Overview](/p/9453) |
| Graduation-gown ID photos | Use cases and rules | [Complete Graduation-Gown ID Photo Guide](/p/9365) |
| Business cards | 9 × 5.4 cm | [What Size Is a Business Card?](/p/9455) |
| Pixel / DPI conversion | 300 DPI standard | [How Many Pixels Does a 4×6 Need to Avoid Blurriness?](/p/9086) |
| Convenience-store printing | ibon / 7-Eleven instructions | [ibon Postcard Sizes / 7-Eleven Printing](/p/4307) |
| Four-cut / photo-booth prints | 2×6 and 4×6 | [Four-Cut Photo Print Sizes](/p/4126) |

For postcard and envelope addressing formats, rather than dimensions, see the [Complete Guide to Postcard Formatting](/p/9029) and the [Complete Guide to Addressing Envelopes](/p/9517).

## Article overview

This article covers the complete specifications for 4×6 photo prints. A 4×6 measures 10.16 × 15.24 cm; Taiwan's terms 6吋照片 and 六寸照 both refer to this size. Printing at 300 DPI requires 1,200 × 1,800 pixels. Compared with A6 paper (10.5 × 14.8 cm), a 4×6 is approximately 4 mm narrower and 4 mm longer, with a different aspect ratio (2:3 versus 1:√2). The guide covers common sizes from 3×5 to 8×10 and explains why printing a 4:3 phone photo as a 4×6 crops about 11% of the image. The long edge of a 4×6 exceeds Chunghwa Post's postcard size limit, so domestic mailing may be charged at letter rates.

- 4×6 = 10.16 × 15.24 cm. Taiwan's common names 6吋照片 and 六寸照 both mean a 6-inch photo; all three names refer to the same print size.
- Printing at 300 DPI requires 1,200 × 1,800 pixels; at 150 DPI, it requires 600 × 900.
- A6 paper measures 10.5 × 14.8 cm and has a different aspect ratio: 4:6 = 2:3, while A6 = 1:√2.
- Common sizes include 3×5, 4×6, 5×7 (12.7 × 17.78 cm), and 8×10.
- Printing a 4:3 phone photo as a 4×6 crops approximately 11% from the edges; printing it as a 6×8 requires no cropping.
- Each R-series size has a different aspect ratio: 3R 1.43, 4R 1.50, 5R 1.40, 6R 1.33, and 8R 1.25. The A series maintains a ratio of 1.414.
- Japan's default photo print is L判, measuring 8.9 × 12.7 cm—one size smaller than 4×6. To print a 4×6 in Japan, select KG判.
- Compare the total cost including shipping, rather than the unit price, when ordering 4×6 prints. Online printing has lower unit prices but minimum quantities and shipping charges; convenience-store 立可得 kiosks can print a single photo for immediate pickup. See the photo-printing channel comparison for prices.

## Frequently asked questions

### How many inches is a 4×6 photo?

Taiwan's photo-printing industry commonly calls it a 6-inch photo, naming it after the long edge. Its actual dimensions are 4 inches × 6 inches = 10.16 × 15.24 cm. The customary spelling 6 寸 does not represent a strict conversion into the traditional Chinese unit cun: 6 cun = 18.18 cm. When you hear 6 寸照片, understand it as the 4×6 print size.

### How many centimeters is a 6-inch photo?

A 6-inch photo is a 4×6 print measuring 10.16 × 15.24 cm. Here, 6 inches refers to the long edge, not the area or the Taiwanese unit cun. It is therefore a rectangle measuring 4 inches × 6 inches, rather than a square with 6-inch sides. The terms 6寸, 六寸照, and 4R all refer to the same size.

### Can I mail a 4×6 photo as a postcard?

For domestic mailing in Taiwan, take care: Chunghwa Post's operating regulations set a maximum postcard size of 14.8 × 10.5 cm, with a permitted tolerance of 2 mm. A 4×6 photo's 15.24 cm long edge exceeds that limit, so a self-printed 4×6 photo may be charged at letter rates. Printing on A6 (10.5 × 14.8 cm) is the safest choice for postcard postage. International mailing has separate size rules; follow the guidance at the post office counter.

### How many pixels do I need to print a 4×6 photo?

Prepare an image of at least 1,200 × 1,800 pixels, the standard for 300 dpi printing. Lower resolutions can look grainy in print. Photos taken with phone cameras generally far exceed this requirement.

### How much does one 4×6 print cost, and where is the best value?

It depends on how many photos you print at once. Compare the total cost including shipping, rather than the unit price. For a few urgent prints, use a convenience-store kiosk: you can print just one and collect it immediately. For several dozen family photos, online printing has much lower unit prices, but you must meet the minimum quantity and add shipping. Unit prices, minimum quantities, shipping fees, and example totals are collected on the Taiwan Photo-Printing Channel Comparison page.