CONVERT DIMENSIONS
Paper Size Converter
Convert paper dimensions between mm, cm and inches, or enter custom measurements to find which standard paper size is the closest match.
How to Convert Paper Dimensions
Paper sizes are defined in millimeters (mm) under the ISO 216 standard, while North American formats use inches. Converting between the two is straightforward: 1 inch = 25.4 mm exactly.
To convert mm to inches, divide by 25.4. To convert inches to mm, multiply by 25.4. For centimeters, 1 cm = 10 mm. The converter above handles all three units automatically and shows the equivalent dimensions side by side.
Common Paper Dimensions at a Glance
The most frequently converted sizes are A4 (210 × 297 mm, 8.27 × 11.69 in),Letter (215.9 × 279.4 mm, 8.5 × 11 in), andLegal (215.9 × 355.6 mm, 8.5 × 14 in). A4 is the international standard; Letter is common in the United States and Canada.
Finding the Nearest Standard Size
When you have a custom document size — from a PDF, a design template, or a non-standard trim — use the "Custom → Convert / Match" mode above. The converter will compare your dimensions against every standard format in our database and rank the closest matches by how far they deviate.
An exact match means you can use that paper name directly in your printer driver. A close match may print successfully with "Fit to Page" scaling enabled.