Paper size dimensions
Get the exact size of any common sheet before you print or design: A4 is 210 × 297 mm, or 8.26771653543 × 11.6929133858 inches, with the same pairing for Letter, Legal, Tabloid and the A, B and C series. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Size
- A4
- Key
- A4
- Series
- ISO A
- Standard
- ISO 216
- Width mm
- 210
Paper size dimensions are the quiet dependency behind every print job, PDF export, envelope order, and design template. Designers, developers, logistics teams, and students constantly need the exact width and height of A4, A3, Letter, Legal, Tabloid, and the rest of the ISO A, B, and C families, preferably in both millimetres and inches so metric and imperial workflows stay aligned. This capability accepts a single size name, looks it up in a fixed deterministic table covering ISO A0 through A10, B0 through B10, C0 through C10, and common North American formats including Letter, Legal, Tabloid, Ledger, Executive, Statement, Folio, Junior Legal, and Government Letter, and returns width and height in millimetres and inches plus area, orientation, aspect ratio, and human-readable dimension strings.
How ISO A, B, C and US paper sizes are defined
The ISO 216 A and B series fix every size from a geometric rule: each next size is the previous sheet cut in half parallel to the short side, preserving an aspect ratio of the square root of two. A0 has an area of one square metre; A4, the everyday office sheet in most of the world, is two hundred ten by two hundred ninety-seven millimetres.
The B series sits between A sizes for posters, books, and intermediate print formats, with B0 at one thousand by one thousand four hundred fourteen millimetres. The ISO 269 C series defines envelope sizes that fit the corresponding A sheets with a small clearance, so C4 holds an unfolded A4 and C5 holds a folded A4.
North American office paper instead starts from fixed inch dimensions: Letter is eight and a half by eleven inches, Legal is eight and a half by fourteen, Tabloid is eleven by seventeen, and Ledger is the landscape twin of Tabloid at seventeen by eleven. Executive, Statement (half letter), Folio (sometimes called government legal), Junior Legal, and Government Letter complete the common US set.
This tool stores ISO sizes as their standard integer millimetre pairs and US sizes as inch definitions converted with the exact factor twenty-five point four millimetres per inch, then exposes both unit systems on every response. It does not resize images, generate PDFs, convert between arbitrary units outside paper, or invent nonstandard commercial stock codes. It answers only the dimension lookup people mean when they search for paper size dimensions and expect A4 next to Letter with millimetres and inches side by side.
Where paper size dimension lookups show up in real work
Print shops and prepress teams constantly map job tickets written as A3 or Tabloid into device margins and stock codes, and they need both millimetre and inch readings when machines and clients mix locales. Web and desktop application developers configure PDF export, page setup, and print CSS with exact page boxes and want one ground-truth table instead of hard-coding scattered constants. Graphic designers building mockups, envelopes, and multi-page templates check whether a C5 envelope fits a folded A4 or whether Executive stock is tall enough for a letterhead block.
Logistics and packaging teams size inserts, labels, and shipping documents against Letter versus A4 so international catalogs stay printable without clipping. Curriculum authors and exam boards generate answer keys and diagram frames that must match real physical sheets in classroom printers. Data pipelines that normalize mixed ERP or DAM metadata with tags like a4, LETTER, and legal can call this capability once per asset instead of reimplementing the table in every service.
If you later need general length unit conversion, image resizing to a page box, or PDF page geometry mutation, treat those as separate search intents and landings rather than overloading this paper size dimensions page.
What you can do with it
PDF and print template metadata
Resolve A4, Letter, Legal, and Tabloid into millimetre and inch page boxes for exporters, print CSS, and device presets.
Envelope and insert fitting
Compare ISO C envelope sizes with A-series sheets so folded letters and cards fit without guessing clearance.
International office stock catalogs
Normalize mixed A3/A4 and US Letter/Legal product data into one dimension table for e-commerce and procurement.
FAQ
Which paper sizes are supported?
ISO A0–A10, B0–B10, C0–C10, plus US Letter, Legal, Tabloid, Ledger, Executive, Statement, Folio, Junior Legal, and Government Letter.
What is the difference between Tabloid and Ledger?
Both use an eleven-by-seventeen-inch sheet. Tabloid is returned as portrait (11×17 in); Ledger as landscape (17×11 in). Areas match.
How are inches derived from millimetres?
Inches = millimetres ÷ 25.4, the exact international definition. ISO sizes use standard integer millimetre tables; US sizes start from inch definitions and convert the other way.
What does it cost?
The browser tool is free and runs locally.
How big is Letter compared with A4?
Letter is 8.5 by 11 inches, or 215.9 by 279.4 millimeters, while A4 is 210 by 297 millimeters. So Letter is slightly wider and A4 slightly taller, which matters for margins and templates.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/conv/paper-size \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"size":"A4"}'const res = await fetch("https://api.kit.forhosting.com/conv/paper-size", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"size": "A4"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/paper-size",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"size": "A4"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/paper-size", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"size":"A4"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"size":"A4"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/paper-size", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"size": "A4"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.paper_size",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
Unknown names fail with a clear invalid_input error instead of inventing a near match.
What you send and what you get back
Send one field named size, a string naming the paper format. Optional alternate keys name and paper are accepted for convenience. Classic checks include A4 as two hundred ten by two hundred ninety-seven millimetres, Letter as eight point five by eleven inches which is two hundred fifteen point nine by two hundred seventy-nine point four millimetres, and Legal as eight point five by fourteen inches. Accepted values include A0 through A10, B0 through B10, C0 through C10 in any common casing, optionally with spaces such as A 4, and US names such as Letter, Legal, Tabloid, Ledger, Executive, Statement, Folio, Junior Legal, and Government Letter, including aliases like half letter for Statement, foolscap or government legal for Folio, and ANSI A for Letter. Missing size, empty strings, and completely unknown labels fail with invalid_input and are not charged; the error message lists the supported families so clients can correct the label rather than guess. On success the response returns the display size name, a stable uppercase key, series and standard labels, width_mm and height_mm, width_in and height_in with twelve significant digits of stable precision, orientation as portrait or landscape, aspect_ratio as height over width, area in square millimetres and square inches, printable dimensions_mm and dimensions_in strings, the mm_per_inch constant, a short formula string, and method table_lookup. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance.
Where paper size dimension lookups show up in real work
Because this capability is a pure parse engine, API pricing is the published base of $0.002 per successful item and failed validation does not consume balance.
Technical questions
Are dimensions returned in millimetres and inches?
Yes. Every success response includes width_mm, height_mm, width_in, height_in, area in both unit systems, and printable dimension strings.