---
title: 'B3 and B2 paper sizes in cm: JIS vs ISO, plus B1, B0 and print pixels'
url: https://joelin.cc/en/p/9886
source: https://joelin.cc/en/p/9886
lang: en
pubDate: '2026-10-30'
date_modified: '2026-10-30'
description: JIS B3 is 36.4 × 51.5 cm and B2 is 51.5 × 72.8 cm. Compare ISO sizes, folding relationships, poster frames and 150/300 DPI pixel dimensions.
schema_type: BlogPosting
author: joe
entity_ids:
  author: https://me.joelin.cc/#joe
ai_role: ai_only
translation_assistant: asaki
ai_credit: 'AI-assisted translation and editing: Asaki (AI)'
faq:
  - q: How many centimetres is B3?
    a: JIS B3 is 36.4 × 51.5 cm (364 × 515 mm); ISO B3 is 35.3 × 50 cm. In Taiwan, B3 generally refers to JIS. Japanese poster frames use the JIS size.
  - q: How many centimetres is B2?
    a: JIS B2 is 51.5 × 72.8 cm (515 × 728 mm); ISO B2 is 50 × 70.7 cm. One B2 corresponds to two B3 sheets in the same standard, allowing for rounding. B2 is common for Japanese shop and merchandise posters.
  - q: Is B3 larger than A3, and B2 larger than A2?
    a: Yes. JIS B3 (36.4 × 51.5 cm) lies between A3 (29.7 × 42 cm) and A2 (42 × 59.4 cm). JIS B2 (51.5 × 72.8 cm) lies between A2 and A1 (59.4 × 84.1 cm). JIS B has about 1.5 times the area of the same-numbered A size.
  - q: Is B3 the same as a Taiwanese quarter-sheet?
    a: No. The Taiwanese 4開 size is 39.3 × 54.6 cm, about 2.9 cm wider and 3.1 cm longer than JIS B3. The 54.6 × 78.7 cm half-sheet is also larger than JIS B2. State both the sheet system and the dimensions.
  - q: How many pixels are needed for a B2 poster?
    a: JIS B2 is 6083 × 8598 px at 300 DPI or 3041 × 4299 px at 150 DPI. Posters viewed at a distance usually need only 150 DPI; close-up text or photographic detail may need 300 DPI.
translation_of: /p/9886
---

# B3 and B2 paper sizes in cm: JIS vs ISO, plus B1, B0 and print pixels

JIS B3 is 36.4 × 51.5 cm (364 × 515 mm); JIS B2 is 51.5 × 72.8 cm (515 × 728 mm). ISO B3 is 35.3 × 50 cm, and ISO B2 is 50 × 70.7 cm.

A Japanese poster, a frame labelled B2 and a printer’s quotation may all lead you to this question. As with B4 and B5, first establish which B standard is intended.

## B3 and B2: two standards

| Size | JIS · cm |
| --- | --- |
| B0 | 103 × 145.6 |
| B1 | 72.8 × 103 |
| B2 | 51.5 × 72.8 |
| B3 | 36.4 × 51.5 |

In Taiwan, B3 and B2 usually mean JIS, reflecting Japanese printing, stationery and frame specifications. The ISO dimensions may appear in international specifications or European equipment. The differences are about 1.1 × 1.5 cm for B3 and 1.5 × 2.1 cm for B2. Choosing the wrong standard can leave a border or crop the poster.

| Size | ISO · cm |
| --- | --- |
| B0 | 100 × 141.4 |
| B1 | 70.7 × 100 |
| B2 | 50 × 70.7 |
| B3 | 35.3 × 50 |

These are diagrams of the size relationship, not scale templates for cutting paper. Standard dimensions are listed in whole millimetres, so rounding can create small differences when halving: 707 mm on ISO B2 becomes 353.5 mm, whereas the listed ISO B3 side is 353 mm.

```mermaid
flowchart TB
    B2["ISO B2<br/>500 × 707 mm"] -->|"Halve the long side"| B3["Two ISO B3<br/>each 353 × 500 mm"]
```

```mermaid
flowchart TB
    B2["JIS B2<br/>515 × 728 mm"] -->|"Halve the long side"| B3["Two JIS B3<br/>each 364 × 515 mm"]
```

## Two B3 sheets make one B2

Like A paper, each step in the B series halves or doubles the area. Its theoretical aspect ratio is 1:√2, so scaling preserves the shape.

| Size · JIS | cm |
| --- | --- |
| B1 | 72.8 × 103 |
| B2 | 51.5 × 72.8 |
| B3 | 36.4 × 51.5 |
| B4 | 25.7 × 36.4 |
| B5 | 18.2 × 25.7 |

B2 folds to B3, B3 to B4, and B4 to B5. Two JIS B4 sheets placed side by side correspond to one B3. These are standard size relationships, subject to whole-millimetre rounding.

- B1: Four B3 sheets
- B2: Two B3 sheets
- B3: Reference
- B4: Half of B3
- B5: A quarter of B3

## Why JIS and ISO differ

The A series uses one set of dimensions, while the B series has two definitions. ISO B sizes sit at the geometric mean between adjacent A sizes: ISO B3 falls between A3 and A2. JIS B sizes have approximately 1.5 times the area of the same-numbered A size. Consequently, every JIS B size is slightly larger than its ISO counterpart. The JIS figures are the familiar ones for Taiwanese copiers, notebooks and frames.

## Where B3 and B2 fit among A sizes

| Size | cm |
| --- | --- |
| A1 | 59.4 × 84.1 |
| B2 · JIS | 51.5 × 72.8 |
| A2 | 42 × 59.4 |
| B3 · JIS | 36.4 × 51.5 |
| A3 | 29.7 × 42 |

B3 is larger than A3 but smaller than A2; B2 is larger than A2 but smaller than A1. JIS B has about 1.5 times the area of the same-numbered A size. If A3 is too small and A2 too large, B3 provides the intermediate option.

## Taiwanese printing sheets are different

Taiwanese printers also use divisions of a 54.6 × 78.7 cm half-sheet. These are not B sizes. The half-sheet is 54.6 × 78.7 cm, versus JIS B2 at 51.5 × 72.8 cm: about 3.1 cm wider and 5.9 cm longer. The quarter-sheet (4開) is 39.3 × 54.6 cm, versus JIS B3 at 36.4 × 51.5 cm: about 2.9 cm wider and 3.1 cm longer.

An order for B3 and one for a Taiwanese quarter-sheet produce different sheets. Give the dimensions in centimetres when having a Japanese poster printed in Taiwan.

## Japanese posters and frames

- B0 and B1 are used for large posters in Japanese stations and passageways, including station advertisements supporting performers. B1 is also used for large exhibition graphics.
- B2 is a common size for Japanese shop posters and anime or idol merchandise posters. A Japanese “B2 ポスター” means 51.5 × 72.8 cm.
- B3 suits smaller posters, shop notices and displays. Japanese frames are sold with B3 and B2 size labels.
- In Taiwan, locally printed posters more often use A sizes or printing-sheet divisions; B3 and B2 often arise when framing merchandise from Japan.

Measure the actual poster and the frame’s internal opening before buying. A B2 label and the usable opening can differ by a few millimetres. Consider the display location and viewing distance as well as the size.

## Pixels for B3 and B2 printing

Use the formula: millimetres ÷ 25.4 × DPI. The result depends on the standard as well as the resolution.

| Size · DPI | Pixels |
| --- | --- |
| JIS B3 · 300 | 4299 × 6083 px |
| JIS B3 · 150 | 2150 × 3041 px |
| JIS B2 · 300 | 6083 × 8598 px |
| JIS B2 · 150 | 3041 × 4299 px |
| ISO B3 · 300 | 4169 × 5906 px |
| ISO B2 · 300 | 5906 × 8350 px |

Posters viewed from one or two metres away are usually adequately served by 150 DPI. Text and photographic detail viewed close up may call for 300 DPI. A JIS B2 file at 300 DPI exceeds 50 million pixels and can be demanding for an ordinary computer; confirm that you need that resolution first.

## Questions

### How many centimetres is B3?

JIS B3 is 36.4 × 51.5 cm (364 × 515 mm); ISO B3 is 35.3 × 50 cm. In Taiwan, B3 generally refers to JIS. Japanese poster frames use the JIS size.

### How many centimetres is B2?

JIS B2 is 51.5 × 72.8 cm (515 × 728 mm); ISO B2 is 50 × 70.7 cm. One B2 corresponds to two B3 sheets in the same standard, allowing for rounding. B2 is common for Japanese shop and merchandise posters.

### Is B3 larger than A3, and B2 larger than A2?

Yes. JIS B3 (36.4 × 51.5 cm) lies between A3 (29.7 × 42 cm) and A2 (42 × 59.4 cm). JIS B2 (51.5 × 72.8 cm) lies between A2 and A1 (59.4 × 84.1 cm). JIS B has about 1.5 times the area of the same-numbered A size.

### Is B3 the same as a Taiwanese quarter-sheet?

No. The Taiwanese 4開 size is 39.3 × 54.6 cm, about 2.9 cm wider and 3.1 cm longer than JIS B3. The 54.6 × 78.7 cm half-sheet is also larger than JIS B2. State both the sheet system and the dimensions.

### How many pixels are needed for a B2 poster?

JIS B2 is 6083 × 8598 px at 300 DPI or 3041 × 4299 px at 150 DPI. Posters viewed at a distance usually need only 150 DPI; close-up text or photographic detail may need 300 DPI.

Sources: Dimensions distinguish Japanese JIS from international ISO. Printing practices and sheet divisions described for Taiwan apply to Taiwan; poster examples refer to Japan.

AI-assisted translation and editing: Asaki (AI)

[Original article](/p/9886)