Reference library

B4 Paper Size

B4 measures 250 x 353 mm, 25 x 35.3 cm, or 9.84 x 13.9 in. See pixel dimensions by DPI, aspect ratio, bleed setup, comparisons, and related tools.

Last checked: 2026-05-01

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At a glance

B4 is 250 x 353 mm, 25 x 35.3 cm, or 9.84 x 13.9 in. At 300 DPI, B4 is 2953 x 4169 px.

Last checked: 2026-05-01 Source: ISO 216:2007 Found a spec change? Send correction.

How we calculate this

Methodology and source handling

We convert physical sizes to inches, multiply by the selected DPI/PPI value, and round to whole pixels.

Methodology Editorial policy

Quick answer

Copy-ready answer

B4 is 250 x 353 mm, 25 x 35.3 cm, or 9.84 x 13.9 in. At 300 DPI, B4 is 2953 x 4169 px.

250 x 353 mm

Dimensions and specs

Millimeters	250 x 353 mm
Centimeters	25 x 35.3 cm
Inches	9.84 x 13.9 in
300 DPI pixels	2953 x 4169 px
Aspect ratio	1:1.412
Standard family	ISO B Series

Pixels

Pixel dimensions by DPI

DPI / PPI	Width	Height	Use
72 DPI	709 px	1001 px	Screen or draft reference density
96 DPI	945 px	1334 px	Screen or draft reference density
150 DPI	1476 px	2085 px	Screen or draft reference density
300 DPI	2953 px	4169 px	Common high-quality print setup
600 DPI	5906 px	8339 px	High-resolution archival or print workflow

Formula

How to calculate this size

Pixel formulapixels = millimeters / 25.4 x PPI

250 mm x 300 PPI = 2,953 px wide.

Trim result2,953 x 4,169 px

Use this when the artwork stops at the finished edge.

Bleed result3,024 x 4,240 px

Add 3 mm per side before calculating pixels when artwork reaches the edge.

Common mistakes

Avoid these b4 paper size problems

Mixing screen pixels with print quality

A paper size needs a PPI target before pixels mean anything for print.

Forgetting orientation

Portrait and landscape use the same dimensions, but width and height swap in the export.

Adding bleed to a paper reference

Paper pages show trim size first; add bleed only when the design prints to the edge.

Calculator

Calculate pixels and bleed

Enter any DPI to calculate the pixel dimensions for this physical size.

Compare

Compare B4 Paper Size

Open a curated comparison or send both sizes into the compare tool with a fragment URL.

compare tool B4 vs B3

B4 Paper Size: 250 x 353 mm
B3: 353 x 500 mm

50% smaller than B3 Paper Size. 0.0022 decimal ratio difference compare tool B4 vs B5

B4 Paper Size: 250 x 353 mm
B5: 176 x 250 mm

100.6% larger than B5 Paper Size. 0.0042 decimal ratio difference compare tool B4 vs A4

B4 Paper Size: 250 x 353 mm
A4: 210 x 297 mm

41.5% larger than A4 Paper Size in Pixels, Millimeters, Centimeters and Inches. 0.0011 decimal ratio difference compare tool B4 vs US Letter

B4 Paper Size: 250 x 353 mm
US Letter: 215.9 x 279.4 mm

46.3% larger than US Letter Paper Size. 0.0645 decimal ratio difference

B4 belongs to the ISO B Series family. Use this reference for print setup, document layout, template sizing, pixel conversion, and comparisons with nearby paper sizes. Pixel dimensions are calculated from the physical size and selected DPI.

Workflow

Use B4 Paper Size in a finished file

Confirm the physical size

Copy the millimeter, centimeter, or inch dimensions for the selected paper standard.

Choose PPI

Use 300 PPI for most sharp print exports, or match the printer requirement.

Calculate pixels

Multiply inches by PPI, then add bleed only when artwork reaches the trimmed edge.

Related pages and tools

same series B3 paper size same series B5 paper size common alternative A4 paper size common alternative US Letter paper size comparison B4 vs B3 comparison B4 vs B5 tool DPI calculator tool Print bleed calculator tool Compare sizes tool

Same branch

Nearby pages

A4 Paper Size in Pixels, Millimeters, Centimeters and Inches A5 Paper Size Legal Paper Size US Letter Paper Size A0 Paper Size A1 Paper Size A10 Paper Size A2 Paper Size

FAQ

Common questions

What is the exact B4 size?

B4 measures 250 x 353 mm, 25 x 35.3 cm, or approximately 9.84 x 13.9 in.

What is B4 in pixels at 300 DPI?

B4 at 300 DPI is 2953 x 4169 px when rounded to the nearest whole pixel.

What aspect ratio is B4?

B4 has an aspect ratio of about 1:1.412 based on its 250 x 353 mm physical dimensions.

Should I add bleed to a B4 design?

For print work, a common starting point is 3 mm bleed on each side, making the document 256 x 359 mm before trimming. Confirm final bleed with your printer.

References

Sources and references

ISO 216 physical dimensions. Pixel values are calculated from millimeters / 25.4 x DPI and rounded to whole pixels.

ISO 216:2007
Used for ISO A and B series physical paper dimensions.
W3C CSS Values and Units Module
Used for CSS unit definitions, absolute unit relationships, and CSS px behavior.

Last checked: 2026-05-01