Paper Size Converter
Convert standard paper sizes (A4, Letter, Legal) between mm, inches and pixels.
Assumptions used in this calculation
- Standard sizes only: Uses official ISO 216 (A-series) and ANSI/US paper dimensions. Custom, regional, or non-standard paper sizes outside these two systems are not included.
About this calculator
Designers, printers and anyone working across international documents regularly need to know exactly how a paper size like A4 or Legal translates into inches, millimetres or pixels, especially when a US-designed template needs to print correctly on ISO paper or vice versa. This converter takes a standard paper size and a target print resolution (DPI), then returns the physical dimensions in millimetres and inches alongside the pixel dimensions needed for digital layout software. Rather than looking up a paper size chart and then separately calculating pixels by hand, converting millimetres to inches and multiplying by DPI, the calculator returns all three measurements together instantly. This is especially useful when setting canvas sizes in design software, since getting the pixel dimensions wrong at a given DPI is a common source of documents that print at the wrong scale or get unexpectedly cropped.
Worked example
A4 at 300 DPI
Result: 210 × 297 mm, 2480 × 3508 px
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