Millimetres alone hide the difference
Before you buy a ream, set a printer tray, or send a PDF abroad, you usually need one clear answer: is this Letter or A4—and will Legal or Tabloid even fit the binder?
A table lists numbers; it rarely shows how much taller Legal is than Letter, or that A4 is slightly narrower and longer than US Letter. The chart above keeps the same proportions as real sheets.
ISO A-series (mm and inches)
A0 halves to A1, A1 to A2, and so on. Each step keeps the same aspect ratio (√2:1). A4 is the office default in most of the world outside North America.
| Name | mm (W × H) | Inches (W × H) | Notes |
|---|---|---|---|
| A3 | 297 × 420 | 11.69 × 16.54 | Two A4 sheets side by side |
| A4 | 210 × 297 | 8.27 × 11.69 | Default office paper outside North America |
| A5 | 148 × 210 | 5.83 × 8.27 | Half of A4; planners and booklets |
| A6 | 105 × 148 | 4.13 × 5.83 | Postcards and small notebooks |
Common US paper sizes
In the United States, “copy paper” and “printer paper” usually mean Letter (8.5×11 in). Legal and Tabloid are the next sizes that matter for contracts, brochures, and wide layouts.
| Name | mm (W × H) | Inches (W × H) | Notes |
|---|---|---|---|
| Letter (8.5×11) | 216 × 279 | 8.5 × 11 | US default “copy paper” |
| Legal (8.5×14) | 216 × 356 | 8.5 × 14 | Contracts; same width as Letter |
| Tabloid / Ledger (11×17) | 279 × 432 | 11 × 17 | Brochures, posters, wide tables |
A4 vs Letter: the mismatch that breaks layouts
A4 is 210×297 mm (about 8.27×11.69 in). US Letter is 216×279 mm (8.5×11 in). Letter is wider and shorter; A4 is narrower and taller.
That gap is small on paper but obvious on screen: footers clip, tables reflow, and “fit to page” shrinks fonts. If you ship PDFs internationally, pick one target size or export with explicit margins.
What size is normal printer paper?
In the US, normal printer paper is Letter—8.5×11 inches, sometimes written as 8.5 x 11. In Europe, Asia, and most other regions, the default is A4.
Printer trays and driver defaults follow local retail: US reams are Letter; ISO markets sell A4. When a file looks “almost right,” check whether the author used the other system.
Compare any two sizes on SizeComparison.org
Use the paper list when you already know the names; use the home chart when you want three objects or a phone for scale.
1. Open the paper database
Go to Paper sizes. Cards show each format at true aspect ratio—A3 through A6, US Letter, Legal, Tabloid, envelopes, and more.
2. Select two sheets
Tap two cards (for example A4 and Letter). Selected cards highlight; the floating bar at the bottom shows mm and inch dimensions.
3. Open the comparison chart
Tap Compare on the bar to load both sheets on the home coordinate chart. Zoom, switch units, or add a phone from the device tabs.
Full list: Browse all paper sizes.
Popular comparisons
Quick links—each opens the home chart with that pair loaded:
Still comparing?
Jump back to the chart above, browse every format in the paper list, or open the home tool to mix paper with phones and other objects.
Common questions
- What is A4 paper size?
- A4 is 210×297 mm (about 8.27×11.69 in). It is the standard office and home printer size in most countries except the US and Canada.
- What is A4 paper size in inches?
- Roughly 8.27 inches wide by 11.69 inches tall. That is slightly narrower and taller than US Letter (8.5×11 in).
- What is A4 paper size in cm?
- 21.0 cm × 29.7 cm. Some product labels round to 21×30 cm; ISO specifies 210×297 mm.
- What is letter size paper?
- US Letter is 8.5×11 inches (216×279 mm). It is what Americans mean by “regular” or “standard” printer paper.
- What is legal size paper?
- US Legal is 8.5×14 inches (216×356 mm)—same width as Letter, three inches taller. Used for legal pads and some contracts.
- What is tabloid size paper?
- Tabloid is 11×17 inches (279×432 mm). Printers and binders may call it Ledger when oriented with the long edge horizontal.
- What is 8.5×11 paper size?
- 8.5 by 11 inches is US Letter—the default copy and printer paper in the United States.
- What is the size of a standard piece of paper?
- It depends on region: US Letter (8.5×11 in) in North America, A4 (210×297 mm) nearly everywhere else. Always check the ream label or PDF page setup.
- What size is printer paper?
- Most home printers expect Letter in the US and A4 in ISO markets. Tray icons and driver defaults usually match local retail packs.
- A4 vs Letter: which is bigger?
- Letter is wider (216 vs 210 mm). A4 is taller (297 vs 279 mm). Area is close, but they are not interchangeable in strict layouts.
- What is A5 paper size?
- A5 is 148×210 mm (about 5.83×8.27 in)—half an A4 sheet. Common for journals, planners, and booklet interiors.
- Legal vs Letter paper size?
- Same width (8.5 in / 216 mm). Legal adds 3 inches of height (14 in total). Legal folders and trays are longer; do not assume Letter equipment fits.
Sources and rounding
Dimensions follow ISO 216 for A-series and common ANSI/US Trade sizes. Manufacturers may trim a millimetre; measure your own ream if precision matters.