Measurements
Read paper dimensions without mixing up the sides
Keep measurement order and units clear when comparing formats.
By Printer Paper Size Team•
Paper dimensions usually appear as a pair: width × height. A reference may list the shorter edge first, while a landscape document lists the longer edge as its width.
Compare the whole pair
210 × 297 mm and 297 × 210 mm describe the same sheet in different orientations. A single number is not enough to identify a format. Always include the unit too: 210 millimeters is not 210 centimeters.
When sharing a specification, write both dimensions, the unit and the orientation. Use the comparison table to see common formats with consistent units.