---
title: What Is Bleed in Printing? 1/8 Inch (About 3 mm) per Side｜Bleed Sizes for Business Cards, Postcards, Letter and A4
url: https://joelin.cc/en/p/9893
source: https://joelin.cc/en/p/9893
lang: en
pubDate: '2026-10-19'
date_modified: '2026-10-19'
description: 'Bleed is artwork past the trim line that gets cut off. Add 1/8 in (about 3 mm) per side: a 3.5 × 2 in business card becomes 3.75 × 2.25 in.'
author: joe
ai_role: ai_only
translation_of: /p/9893
---

# What Is Bleed in Printing? 1/8 Inch (About 3 mm) per Side｜Bleed Sizes for Business Cards, Postcards, Letter and A4

Bleed is the strip of artwork that extends past the trim line and gets cut off after printing. The usual requirement is 1/8 inch (0.125 in) per side in the US, about 3 mm, and 3 mm per side where printers work in millimeters. So the file size is the finished size plus 1/4 in (or 6 mm) in each direction.

Printing does not happen one sheet at a time on paper that is exactly the finished size. Pieces are printed on large sheets and then trimmed, and the cutter can be off by a fraction of a millimeter. If the background color stops exactly at the finished edge, a slightly off-center cut leaves a thin white line. Bleed means extending the color one strip further, so wherever the cutter lands, it cuts through color.

## Bleed, trim line, and safe area: the three lines on a print file

- The bleed line is the outermost line. Background colors and full-page photos have to extend all the way to it, and everything outside the trim line is cut off after printing.
- The trim line is in the middle. It is the finished size, for example 3.5 × 2 in for a US business card.
- The safe area is the innermost zone, a further 1/8 in (about 3 mm) inside the trim line. Text, logos, and important images belong inside it so they are not cut off or left hugging the edge.

![Bleed diagram for a 9 × 5.4 cm business card: the outer bleed area at 9.6 × 6 cm is trimmed off, the trim line in the middle at 9 × 5.4 cm is the finished size, and the safe area sits 3 mm further inside, where the text and logo go.](https://image.joelin.cc/cdn-cgi/imagedelivery/0xu8EsaSar9n3zUKY5d7xw/joelin/2026-10/print-bleed-3mm-guide-diagram/hero)

The diagram uses a 9 × 5.4 cm business card, a common size in Taiwan, where this article was first written. The three lines work the same way at any size: with 3 mm of bleed it becomes a 9.6 × 6 cm file (1134 × 709 px at 300 DPI).

## File sizes for common pieces

With a 1/8 in bleed on every side for inch sizes, and 3 mm for metric sizes:

| Piece | Finished size | File size with bleed | Pixels at 300 DPI |
| --- | --- | --- | --- |
| US business card | 3.5 × 2 in | 3.75 × 2.25 in | 1125 × 675 |
| 4 × 6 postcard | 4 × 6 in | 4.25 × 6.25 in | 1275 × 1875 |
| Letter | 8.5 × 11 in | 8.75 × 11.25 in | 2625 × 3375 |
| A6 | 10.5 × 14.8 cm | 11.1 × 15.4 cm | 1311 × 1819 |
| A5 | 14.8 × 21 cm | 15.4 × 21.6 cm | 1819 × 2551 |
| A4 | 21 × 29.7 cm | 21.6 × 30.3 cm | 2551 × 3579 |
| A3 | 29.7 × 42 cm | 30.3 × 42.6 cm | 3579 × 5031 |

There is only one rule: add 1/4 in (or 0.6 cm) to both the width and the height. A 1/8 in bleed is 3.175 mm, so the inch and metric conventions are practically the same. When you create a new file, set it to the file size from the start and drag out guides for the trim line and safe area. That is much easier than extending the background after the design is finished. For the full specifications of each size, see [4 × 6 photo size](/en/p/9035), [A6 size](/en/p/9020), [A5 size](/en/p/9447), [A4 size](/en/p/9607), and [A3 size](/en/p/9609).

## What happens if you leave out bleed

- On business cards and postcards with a full-color background, a cut that is off by 0.5 mm leaves a white line along one edge, and each card can be off in a different direction.
- A photo placed exactly at the finished edge may lose a sliver when trimmed, or show a white strip.
- When a printer receives a file without bleed, they usually send it back and ask you to add it, or simply enlarge the image slightly to cover the gap, which crops whatever was near the edges.

## When you do not need bleed

- If the design already has a white border around all four sides, an off-center cut will not show, so no bleed is needed.
- Office copying and printing on your own printer use paper that is already the finished size, and the printer leaves a white margin automatically.
- Self-service printing at copy shops and kiosks usually prints on fixed-size paper and does not use a bleed workflow either.

On the other hand, large-format printing, posters, and some printers may require 5 mm of bleed, or ask you to leave extra room for the gripper edge and crop marks. Always follow the printer's file guidelines. The printing paper itself always starts out larger than the finished piece; [Poster Sizes](/en/p/9742) explains why the finished piece ends up slightly smaller than the full sheet.

## Frequently asked questions

### What is bleed in printing?

Bleed is the strip of artwork that extends past the trim line and is cut off after printing. Pieces are printed on large sheets and then trimmed, and the cutter can be off by a fraction of a millimeter. Extending full-color areas into the bleed means an off-center cut will not leave a white edge.

### How much bleed should I add?

The usual requirement is 1/8 in (0.125 in, about 3 mm) per side in the US, and 3 mm per side for metric sizes, so the file is the finished size plus 1/4 in (or 0.6 cm) in each direction. Large-format printers and some print shops may ask for 5 mm, so check the printer's file guidelines before ordering.

### What is A4 with bleed?

A finished A4 page is 21 × 29.7 cm. With 3 mm of bleed on each side, the file is 21.6 × 30.3 cm, or 2551 × 3579 pixels at 300 DPI. A US Letter page (8.5 × 11 in) with 1/8 in bleed is 8.75 × 11.25 in, or 2625 × 3375 pixels.

### What size is a business card with bleed?

A standard US business card is 3.5 × 2 in. With 1/8 in of bleed on each side, the file is 3.75 × 2.25 in, or 1125 × 675 pixels at 300 DPI. Keep text and logos at least 1/8 in (about 3 mm) inside the trim line.

Keywords: bleed in printing, print bleed, bleed size, 1/8 inch bleed, 3 mm bleed, file size with bleed, safe area, trim line, business card bleed, A4 bleed, Letter bleed, print file setup

Sources: Chinese original first published 2026-10-09. The Chinese original uses a 9 × 5.4 cm business card and metric sizes; this English version adds US business card, 4 × 6 in postcard and Letter sizes with a 1/8 in bleed, calculated by conversion. Bleed requirements vary by printer.