Paper Size Reference
Look up paper sizes (A4 / B5 / Letter / Legal / postcard / business card / envelopes) with millimetres, centimetres, inches, points, and pixel dimensions at 72 / 96 / 150 / 300 / 600 DPI. Distinguishes ISO 216 (A / B / C series) from JIS B; includes Japanese photo formats (L / 2L / KG) and postal envelope standards. Search across names, aliases, and notes with a series filter. Useful for print, DTP, PDF export, and image sizing decisions.
How to use
Type a size name (A4, B5, Letter), alias (4x6, ledger, naga3), or usage (postcard, business card, nengajo) in the search box to filter. Use the series select to scope to ISO A / ISO B / ISO C envelopes / JIS B / US / Photo & cards / Japanese envelopes. Choose the pixel DPI from 72 / 96 / 150 / 300 / 600 — 96 DPI is the web standard, 300 DPI is print standard. All data is static and bundled with the page; nothing leaves your browser.
FAQ
- Is ISO B5 the same as JIS B5?
- No. ISO 216 B5 is 176 × 250 mm, while Japanese JIS B5 is 182 × 257 mm. Notebooks and books in Japan labelled "B5" are almost always JIS B5. Both series are listed separately here.
- How are pixel sizes calculated?
- For the selected DPI, `mm × DPI / 25.4` is computed and rounded to the nearest integer pixel. Default is 300 DPI (print standard). Use 96 DPI for web display, 300 DPI for photo prints, and 350 DPI for commercial print.
- Are ANSI / Arch sizes included?
- ANSI A (= Letter), ANSI B (= Tabloid), and ANSI C / D / E are included in the US category. Architectural Arch sizes (9×12 / 12×18 etc.) may be added later.
- Searching "nengajo" finds the Japanese postcard entry — why?
- The "postcard" entry has aliases for nengajo (年賀状), postcard, and hagaki, so any of those terms matches the same row. Japanese envelopes are also indexed by aliases like chokei3 / naga3 / 長3.
- What is the Ratio column for?
- Height ÷ width. ISO 216 (A / B / C series) all share 1:√2 ≈ 1.414, the property that halves preserve the ratio. L-size photo is ~1.427, Letter ~1.294, Legal ~1.647 — useful for layout decisions.
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