About & method
A measurement site should show its work.
Paper Size Lab is an independent reference for designers, students, office teams, printers, and anyone trying to make one document fit the right sheet.
Start with the standard
ISO-series pages cite ISO 216. North American sheet references identify the defining inch measurements and link to ASME’s sheet-size standard where applicable.
Convert from one source value
Millimeters are the stored base for metric sheets. Inch-defined formats are represented using exact inch-to-millimeter conversion. We calculate other units from that source rather than copying rounded tables.
Separate fact from workflow
Dimensions are fixed; printer support, bleed, postal rules, and regional use are contextual. We label those notes and tell readers to confirm requirements with the relevant service or print vendor.
Publishing policy
What earns an indexable page
- Exact dimensions and mathematically checked conversions
- A useful pixel table rather than one arbitrary DPI
- Regional and printer context
- A real comparison or decision aid
- A named measurement source and visible update date
We do not publish a page merely because a keyword exists. A page has to answer a distinct task better than a bare conversion table.