Paper Size Converter
Look up and convert paper sizes (A4, A3, Letter, Legal, B series) between mm, cm, inches, points, and pixels at 96 DPI.
Reviewed October 7, 2026 Runs in your browser — inputs are never stored
A4
210.0 × 297.0 mm
mm
210.0 × 297.0
cm
21.0 × 29.7
in
8.268 × 11.693
pt
595.3 × 841.9
px
794.0 × 1123.0
ISO 216 A series (mm)
| Size | Width | Height |
|---|---|---|
| A3 | 297 mm | 420 mm |
| A4 | 210 mm | 297 mm |
| A5 | 148 mm | 210 mm |
| A6 | 105 mm | 148 mm |
This tool provides general unit conversions for everyday and educational use. For regulated, legal, or scientific applications, verify conversion factors against the applicable official standard.
About the Paper Size Converter
The paper size converter shows the dimensions of ISO A and B sizes and US sizes such as Letter, Legal and Tabloid in millimetres, centimetres, inches, points and pixels at common DPIs. ISO sizes share an aspect ratio of 1 : √2, so each size is exactly half of the previous one: two A4 sheets make an A3.
How to use it
- 1Choose to look up a standard size or enter custom dimensions.
- 2Select the paper size.
- 3Choose the unit and read the width and height.
- 4Copy, share or print the result with the buttons below it.
Worked example
A4 is 210 × 297 mm (8.27 × 11.69 in), and US Letter is 8.5 × 11 in (215.9 × 279.4 mm).
How it works
ISO 216 standard
The ISO A series follows: each size is half the previous. A0 = 841×1189mm · A4 = 210×297mm · A5 = 148×210mm. Each halves the longer dimension.
US paper sizes
Letter = 8.5×11 in (215.9×279.4 mm) · Legal = 8.5×14 in · Tabloid = 11×17 in.
Common use cases
- Setting up documents for print
- Choosing image sizes for printing
- Comparing US and international paper
Frequently asked questions
A:A4 = 8.27 × 11.69 inches (210 × 297 mm).
A:No. Letter (US) = 8.5×11 in = 216×279 mm. A4 = 8.27×11.69 in = 210×297 mm. A4 is slightly narrower and taller.
Reviewed for accuracy · Last updated October 7, 2026
Conversion factors are based on internationally defined SI units and standard metric/imperial equivalence tables.
CalcWisee Editorial Team
Calculator development and formula review
CalcWisee is an independent site founded by Ayman. Every calculator is built from a published formula or official definition, tested against hand-worked examples before it goes live, and corrected promptly when a reader reports an issue to ayman@calcwisee.com.
Expertise: Financial mathematics, Health and fitness formulas, Applied mathematics, Unit conversion standards
References & sources
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