Reference library

B10 Paper Size

B10 measures 31 x 44 mm, 3.1 x 4.4 cm, or 1.22 x 1.73 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

B10 is 31 x 44 mm, 3.1 x 4.4 cm, or 1.22 x 1.73 in. At 300 DPI, B10 is 366 x 520 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

B10 is 31 x 44 mm, 3.1 x 4.4 cm, or 1.22 x 1.73 in. At 300 DPI, B10 is 366 x 520 px.

31 x 44 mm

Dimensions and specs

Millimeters	31 x 44 mm
Centimeters	3.1 x 4.4 cm
Inches	1.22 x 1.73 in
300 DPI pixels	366 x 520 px
Aspect ratio	1:1.4194
Standard family	ISO B Series

Pixels

Pixel dimensions by DPI

DPI / PPI	Width	Height	Use
72 DPI	88 px	125 px	Screen or draft reference density
96 DPI	117 px	166 px	Screen or draft reference density
150 DPI	183 px	260 px	Screen or draft reference density
300 DPI	366 px	520 px	Common high-quality print setup
600 DPI	732 px	1039 px	High-resolution archival or print workflow

Formula

How to calculate this size

Pixel formulapixels = millimeters / 25.4 x PPI

31 mm x 300 PPI = 366 px wide.

Trim result366 x 520 px

Use this when the artwork stops at the finished edge.

Bleed result437 x 591 px

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

Common mistakes

Avoid these b10 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 B10 Paper Size

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

compare tool B10 vs B9

B10 Paper Size: 31 x 44 mm
B9: 44 x 62 mm

50% smaller than B9 Paper Size. 0.0051 decimal ratio difference compare tool B10 vs A4

B10 Paper Size: 31 x 44 mm
A4: 210 x 297 mm

97.8% smaller than A4 Paper Size in Pixels, Millimeters, Centimeters and Inches. 0.0025 decimal ratio difference compare tool B10 vs US Letter

B10 Paper Size: 31 x 44 mm
US Letter: 215.9 x 279.4 mm

97.7% smaller than US Letter Paper Size. 0.0682 decimal ratio difference

B10 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 B10 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 B9 paper size common alternative A4 paper size common alternative US Letter paper size comparison B10 vs B9 comparison B10 vs A4 tool DPI calculator tool Print bleed calculator

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 B10 size?

B10 measures 31 x 44 mm, 3.1 x 4.4 cm, or approximately 1.22 x 1.73 in.

What is B10 in pixels at 300 DPI?

B10 at 300 DPI is 366 x 520 px when rounded to the nearest whole pixel.

What aspect ratio is B10?

B10 has an aspect ratio of about 1:1.4194 based on its 31 x 44 mm physical dimensions.

Should I add bleed to a B10 design?

For print work, a common starting point is 3 mm bleed on each side, making the document 37 x 50 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