The dimensions of paper in the US start with Letter size: 8.5 × 11 inches (216 × 279 mm). Most of the world uses A4, which is 210 × 297 mm (8.27 × 11.69 inches).

This guide lists every common paper size in inches, mm, cm and pixels. You will see US sizes, A series paper sizes, C series envelopes and how to pick the right one.

US Paper Sizes: Letter, Legal and Tabloid Dimensions

The US, Canada and parts of Mexico use ANSI paper sizes, not ISO sizes. Letter is the everyday standard paper size for school, home and office printing.

Size	Inches	mm
Letter	8.5 × 11	215.9 × 279.4
Legal	8.5 × 14	215.9 × 355.6
Tabloid (Ledger)	11 × 17	279.4 × 431.8
Executive	7.25 × 10.5	184 × 267
Statement (Half Letter)	5.5 × 8.5	140 × 216
Junior Legal	5 × 8	127 × 203

Here is where each one fits:

• Letter: resumes, reports, forms and homework.
• Legal: contracts and legal documents.
• Tabloid: menus, newsletters and small posters.
• Statement: small booklets and invoices.

Larger ANSI sizes follow the same pattern. ANSI C is 17 × 22 in, ANSI D is 22 × 34 in and ANSI E is 34 × 44 in. Engineers use them for drawings.

What is Letter size in pixels? It is 612 × 792 px at 72 dpi. At 300 dpi, a print-ready file is 2550 × 3300 px.

Accurate measurements matter beyond paper and printing—they’re just as important when choosing furniture that fits your space. If you’re planning a home office or workspace, explore this guide to standard bench sizes and measurements to find the right fit for your layout.

A4 Paper Size in Inches, CM, MM and Pixels

A4 measures 210 × 297 mm. That is 21 × 29.7 cm or 8.27 × 11.69 inches.

In pixels, A4 is 595 × 842 px at 72 dpi. At 300 dpi, it is 2480 × 3508 px.

A4 belongs to the A series, set by the ISO 216 standard. It follows three simple rules:

• A0 has an area of 1 square metre (841 × 1189 mm).
• Every size is the one before it cut in half across its long side.
• The aspect ratio is 1:1.414 (the square root of 2).

That ratio keeps the shape the same at every size. A page scaled from A4 to A3 does not stretch or crop.

Size	mm	cm	Inches
A0	841 × 1189	84.1 × 118.9	33.11 × 46.81
A1	594 × 841	59.4 × 84.1	23.39 × 33.11
A2	420 × 594	42.0 × 59.4	16.54 × 23.39
A3	297 × 420	29.7 × 42.0	11.69 × 16.54
A4	210 × 297	21.0 × 29.7	8.27 × 11.69
A5	148 × 210	14.8 × 21.0	5.83 × 8.27
A6	105 × 148	10.5 × 14.8	4.13 × 5.83
A7	74 × 105	7.4 × 10.5	2.91 × 4.13
A8	52 × 74	5.2 × 7.4	2.05 × 2.91
A9	37 × 52	3.7 × 5.2	1.46 × 2.05
A10	26 × 37	2.6 × 3.7	1.02 × 1.46

Sizes are rounded to the nearest millimetre. ISO allows small tolerances: ±1.5 mm up to 150 mm, ±2 mm from 150 to 600 mm, and ±3 mm above 600 mm.

Two oversize formats exist: 2A0 (1189 × 1682 mm) and 4A0 (1682 × 2378 mm). They come from the German DIN 476 standard, not ISO 216. A3+ (Super A3) is about 329 × 483 mm and is also not an ISO size.

Here is what each size is used for:

• A0 and A1: posters, technical drawings and architectural plans.
• A2: wall charts and display boards.
• A3: charts, spreadsheets and brochures.
• A4: letters, forms, printing and magazines.
• A5: notebooks, booklets and flyers.
• A6: postcards and invitations.
• A7 and A8: pocket notes and gift tags.

The B series sits between A sizes. B5 is 176 × 250 mm and B4 is 250 × 353 mm. Japan uses JIS B sizes, which run about 6% larger. JIS B5 is 182 × 257 mm. Check which B size you need before you buy notebooks.

C Series Paper Size for Envelopes

Envelope sizes outside the US follow the C series (ISO 269). Each C size is built to hold a matching A series sheet.

Envelope	mm	Inches	Fits
C4	324 × 229	12.76 × 9.02	A4 flat or A3 folded once
C5	162 × 229	6.38 × 9.02	A5 flat or A4 folded once
C6	114 × 162	4.49 × 6.38	A6 flat or A4 folded twice
DL	110 × 220	4.33 × 8.66	A4 folded in thirds
C7/6	89 × 165	3.50 × 6.50	One-third of an A4 sheet

Which envelope fits A4? C4 holds A4 flat. C5 holds it folded once. DL holds it folded in thirds.

In the US, the common business envelope is the #10, at 4.125 × 9.5 in. A Letter sheet folded in thirds fits it.

Letter vs A4: How to Choose the Right Paper Size

Letter and A4 look close, but they are not the same. A4 is about 0.23 in narrower and 0.69 in taller than Letter.

	Letter	A4
Inches	8.5 × 11	8.27 × 11.69
mm	216 × 279	210 × 297
Ratio	1:1.29	1:1.41

Here is a simple way to choose:

• Printing in the US: use Letter.
• Sending documents abroad: use A4.
• Applying for a visa or an overseas job: use A4.
• Printing posters: pick A2, A1 or Tabloid by wall space.

If you print an A4 file on Letter paper, the sides can shift and the bottom can clip. Choose “Fit to page” in your printer settings to avoid this.

Set the page size first. In Word, Google Docs or Canva, pick Letter or A4 before you design. Changing it later can break the layout.

Check paper weight too. In the US, weight is in pounds (lb bond). Elsewhere it is in gsm. A 20 lb bond sheet is close to 75 gsm, which is typical office paper.

Dimensions of Paper FAQs

What are the dimensions of a standard paper?

In the US, standard paper is Letter: 8.5 × 11 inches (216 × 279 mm). In most other countries it is A4: 210 × 297 mm (8.27 × 11.69 inches).

What is the size of A1, A2, A3, and A4?

• A1: 594 × 841 mm (23.39 × 33.11 in)
• A2: 420 × 594 mm (16.54 × 23.39 in)
• A3: 297 × 420 mm (11.69 × 16.54 in)
• A4: 210 × 297 mm (8.27 × 11.69 in)

Is A4 paper 1920×1080?

No. 1920 × 1080 is a screen resolution with a 16:9 shape. A4 has a 1:1.414 shape. At 300 dpi, A4 is 2480 × 3508 pixels.

What is the dimension of an A4 paper?

What is A1, A2, A3, and A4?

They are ISO 216 paper sizes. Each size is half the size before it. A1 and A2 suit posters. A3 suits charts and drawings. A4 suits everyday documents.

What are paper sizes A3, A4, A5, and A6?

• A3: 297 × 420 mm (11.69 × 16.54 in)
• A4: 210 × 297 mm (8.27 × 11.69 in)
• A5: 148 × 210 mm (5.83 × 8.27 in)
• A6: 105 × 148 mm (4.13 × 5.83 in)

Conclusion

In short, remember Letter for US printing and A4 for everything international. Every other paper size follows from those two by halving or doubling.