Paper Sizes: A3 vs A4 vs A5 vs Letter vs Legal

A3, A4, A5, Letter and Legal paper sizes in millimeters, centimeters and inches — plus what each size is actually used for.

Every size is exactly half the one above it. A0 covers precisely one square metre; A1 is half of that, A2 a quarter. Because the ratio is 1:√2 on every sheet, folding never leaves an awkward remainder.

An A0 sheet reaches roughly to an adult's chest — a quicker way to judge wall space than reading millimetres.

A series — the international standard

Defined by ISO 216 and used everywhere except North America. Every size is exactly half the one above it, folded across the long edge, because the ratio of every sheet is 1:√2. That is the whole trick: fold an A4 in half and you get a perfect A5, never an awkward leftover.

Size	mm	cm	inches	pixels @300 DPI	Most used for
A0	841 × 1189	84.1 × 118.9	33.11 × 46.81	9,934 × 14,044	Technical drawings, posters — exactly 1 m²
A1	594 × 841	59.4 × 84.1	23.39 × 33.11	7,016 × 9,934	Technical drawings, posters, flip charts
A2	420 × 594	42 × 59.4	16.54 × 23.39	4,961 × 7,016	Flip charts, posters
A3	297 × 420	29.7 × 42	11.69 × 16.54	3,508 × 4,961	Newspapers, wide tables and drawings — the largest size most copiers take
A4	210 × 297	21 × 29.7	8.27 × 11.69	2,481 × 3,508	Letters, magazines, forms, catalogues, printer and copier output
A5	148 × 210	14.8 × 21	5.83 × 8.27	1,749 × 2,481	Note pads, books
A6	105 × 148	10.5 × 14.8	4.13 × 5.83	1,241 × 1,749	Postcards, books
A7	74 × 105	7.4 × 10.5	2.91 × 4.13	875 × 1,241	Small notes and labels — half of A6
A8	52 × 74	5.2 × 7.4	2.05 × 2.91	615 × 875	Playing cards; some use it for business cards

B series — between the A sizes

B sizes sit between consecutive A sizes, which makes them the natural choice when A4 is too small and A3 too large. In practice you meet them in books, newspapers and posters. Japan uses its own, slightly larger B series (JIS P 0138), listed below — printer settings show the two separately, so check which “B5” a template means.

Size	mm	cm	inches	pixels @300 DPI	Most used for
B0	1000 × 1414	100 × 141.4	39.37 × 55.67	11,812 × 16,701	Very large posters
B1	707 × 1000	70.7 × 100	27.83 × 39.37	8,351 × 11,812	Large posters
B2	500 × 707	50 × 70.7	19.69 × 27.83	5,906 × 8,351	Posters
B3	353 × 500	35.3 × 50	13.90 × 19.69	4,170 × 5,906	Posters
B4	250 × 353	25 × 35.3	9.84 × 13.90	2,953 × 4,170	Newspapers; supported by most copiers
B5	176 × 250	17.6 × 25	6.93 × 9.84	2,079 × 2,953	Books
B6	125 × 176	12.5 × 17.6	4.92 × 6.93	1,477 × 2,079	Books
JIS B4	257 × 364	25.7 × 36.4	10.12 × 14.33	3,036 × 4,300	Japanese B4 (JIS P 0138) — 7 × 11 mm larger than ISO B4
JIS B5	182 × 257	18.2 × 25.7	7.17 × 10.12	2,150 × 3,036	Japanese B5 — 6 × 7 mm larger than ISO B5
JIS B6	128 × 182	12.8 × 18.2	5.04 × 7.17	1,512 × 2,150	Japanese B6 — listed separately in printer settings

C series — envelopes

The C series exists for one job: holding A-series paper. A C4 envelope takes an unfolded A4, C5 takes an A4 folded once, and C6 takes it folded twice. DL is not part of the series but is the most common business envelope in Europe.

Size	mm	cm	inches	pixels @300 DPI	Most used for
C4	229 × 324	22.9 × 32.4	9.02 × 12.76	2,705 × 3,827	Holds an unfolded A4 — contracts, certificates
C5	162 × 229	16.2 × 22.9	6.38 × 9.02	1,914 × 2,705	Holds A4 folded once, or an unfolded A5
C6	114 × 162	11.4 × 16.2	4.49 × 6.38	1,347 × 1,914	Holds A4 folded twice — greeting cards, invitations
DL	110 × 220	11 × 22	4.33 × 8.66	1,300 × 2,599	Standard business envelope — A4 folded in three

North American sizes

The United States, Canada and parts of Latin America never adopted ISO 216. These sizes come from imperial inches instead, which is why Letter is slightly wider and shorter than A4 — close enough to look identical, different enough to break a layout.

Size	mm	cm	inches	pixels @300 DPI	Most used for
Letter	215.9 × 279.4	21.59 × 27.94	8.50 × 11.00	2,550 × 3,300	The US everyday sheet — 8.5 × 11 in
Legal	215.9 × 355.6	21.59 × 35.56	8.50 × 14.00	2,550 × 4,201	Contracts and legal documents — 8.5 × 14 in
Tabloid / Ledger	279.4 × 431.8	27.94 × 43.18	11.00 × 17.00	3,300 × 5,100	ANSI B — wide spreadsheets, newsletters, small posters — 11 × 17 in
Folio	215.9 × 330.2	21.59 × 33.02	8.50 × 13.00	2,550 × 3,900	Letter width, 1 in shorter than Legal — 8.5 × 13 in
Executive	184.2 × 266.7	18.42 × 26.67	7.25 × 10.50	2,176 × 3,150	Printer-driver preset — 7.25 × 10.5 in (older lists give 7.5 × 10 in)
Half Letter / Statement	139.7 × 215.9	13.97 × 21.59	5.50 × 8.50	1,650 × 2,550	A Letter sheet folded once — booklets, planners — 5.5 × 8.5 in
Junior Legal	127 × 203.2	12.7 × 20.32	5.00 × 8.00	1,500 × 2,400	Small note pads — 5 × 8 in
ANSI C	431.8 × 558.8	43.18 × 55.88	17.00 × 22.00	5,100 × 6,600	Engineering drawings — 17 × 22 in
ANSI D	558.8 × 863.6	55.88 × 86.36	22.00 × 34.00	6,600 × 10,200	Large engineering drawings — 22 × 34 in
ANSI E	863.6 × 1117.6	86.36 × 111.76	34.00 × 44.00	10,200 × 13,200	The largest ANSI drawing sheet — 34 × 44 in

Sizes people name in inches

A whole set of everyday sizes has no letter name at all — people just say the inches. Index cards, photo prints and poster sizes all work this way, and the big architectural sheets have their own ARCH series. Here is what each one actually measures.

Size	mm	cm	inches	pixels @300 DPI	Most used for
3 × 5 in	76.2 × 127	7.62 × 12.7	3.00 × 5.00	901 × 1,500	Index cards, recipe cards, small notes
4 × 5 in	101.6 × 127	10.16 × 12.7	4.00 × 5.00	1,200 × 1,500	Large-format sheet film, studio proof prints
4 × 6 in	101.6 × 152.4	10.16 × 15.24	4.00 × 6.00	1,200 × 1,801	The standard photo print, postcards, index cards
5 × 7 in	127 × 177.8	12.7 × 17.78	5.00 × 7.00	1,500 × 2,101	Framed desk photos, greeting cards, invitations
8 × 10 in	203.2 × 254	20.32 × 25.4	8.00 × 10.00	2,400 × 3,000	Portraits, certificates, framed prints
8.5 × 11 in	215.9 × 279.4	21.59 × 27.94	8.50 × 11.00	2,550 × 3,300	US Letter (ANSI A) — everyday documents in the US and Canada
9 × 12 in (ARCH A)	228.6 × 304.8	22.86 × 30.48	9.00 × 12.00	2,700 × 3,601	The smallest architectural sheet
11 × 17 in	279.4 × 431.8	27.94 × 43.18	11.00 × 17.00	3,300 × 5,100	Tabloid / Ledger (ANSI B) — spreadsheets, menus, small posters
12 × 18 in (ARCH B)	304.8 × 457.2	30.48 × 45.72	12.00 × 18.00	3,601 × 5,400	Architectural drawings, mid-size posters
18 × 24 in (ARCH C)	457.2 × 609.6	45.72 × 60.96	18.00 × 24.00	5,400 × 7,201	Posters, architectural plans, art prints
24 × 36 in (ARCH D)	609.6 × 914.4	60.96 × 91.44	24.00 × 36.00	7,201 × 10,800	Large posters, architectural drawings

Photo print sizes

Photo labs work in their own set of sizes, usually quoted in inches even in metric countries. Note that most do not share an aspect ratio with your camera, so something always gets cropped — check before you order.

Size	mm	cm	inches	pixels @300 DPI	Most used for
9 × 13 cm	89 × 127	8.9 × 12.7	3.50 × 5.00	1,052 × 1,500	Small wallet prints (3.5 × 5 in)
10 × 15 cm	102 × 152	10.2 × 15.2	4.02 × 5.98	1,205 × 1,796	The standard photo print (4 × 6 in)
13 × 18 cm	127 × 178	12.7 × 17.8	5.00 × 7.01	1,500 × 2,103	Framed desk photos (5 × 7 in)
20 × 25 cm	203 × 254	20.3 × 25.4	7.99 × 10.00	2,398 × 3,000	Portraits and framed prints (8 × 10 in)
30 × 40 cm	305 × 406	30.5 × 40.6	12.01 × 15.98	3,603 × 4,796	Wall art (12 × 16 in)
45 × 60 cm	457 × 610	45.7 × 61	17.99 × 24.02	5,398 × 7,205	Large wall prints (18 × 24 in)

Which paper for what

The usual size for each job, in the ISO system used by most of the world and in North America. A dash means there is no common North American standard for it.

Job	Most of the world (ISO)	US & Canada
Letters, forms, everyday printing	A4	Letter (8.5 × 11 in)
Contracts and legal filings	A4	Legal (8.5 × 14 in)
Newspapers, wide tables, drawings	A3, B4	Tabloid (11 × 17 in)
Books	B5, A5, B6, A6	—
Note pads and planners	A5	Half Letter (5.5 × 8.5 in), Junior Legal (5 × 8 in)
Postcards	A6	—
Posters and flip charts	A2, A1, A0	18 × 24 in, 24 × 36 in
Technical drawings	A0–A3	ANSI A–E, ARCH A–E
Envelopes for A4	C4 (flat), C5 (folded once), C6 (folded twice), DL (in thirds)	—
Business cards	85 × 55 mm, ID-1 85.60 × 53.98 mm	3.5 × 2 in
Photo prints	10 × 15 cm, 13 × 18 cm	4 × 6 in, 5 × 7 in
Playing cards	A8	—

Everyday names — what people actually say

Most people never say “A6”. They say “a quarter page”, “office paper” or “poster size”. Here is what each everyday term actually means.

What people say	What it means	Size
“Office paper” / “copy paper”	A4 — the default sheet in every printer outside North America.	210 × 297 mm
“Half a page” / “half A4”	A5. Fold an A4 across its long edge and you get exactly A5 — no trimming, no leftover.	148 × 210 mm
“Quarter page” / “quarter A4”	A6. That is A4 folded twice — the standard postcard size.	105 × 148 mm
“Eighth of a page”	A7 — pocket notes, cloakroom tickets, small labels.	74 × 105 mm
“Half letter” / “statement”	The North American equivalent of half a page: a Letter sheet folded once.	139.7 × 215.9 mm (5.5 × 8.5 in)
“Poster size”	There is no single answer — A2 for a shop window, A1 for a street poster, A0 for an exhibition panel. In North America the equivalents are usually 18 × 24 or 24 × 36 in.	A2 420 × 594 · A1 594 × 841 · A0 841 × 1189 mm
“Business card”	Not an ISO 216 paper size. Many cards follow the bank-card format ID-1 from ISO/IEC 7810 (85.60 × 53.98 mm); European printers commonly quote 85 × 55 mm, North America 3.5 × 2 in (88.9 × 50.8 mm) — close, but not interchangeable in a print template.	85 × 55 mm (EU) · 88.9 × 50.8 mm (US) · ID-1 85.60 × 53.98 mm
“Oversize A3” / SRA3	SRA3, from ISO 217. It is deliberately larger than A3 so artwork can bleed off the edge and be trimmed back to an exact A3.	320 × 450 mm

Head to head

The questions that come up when two sizes look interchangeable but are not.

A4 vs US Letter

Short answer: They look the same and are not. A4 is 6 mm narrower and 18 mm taller than Letter. Print an A4 layout on Letter and the bottom is cut off; print Letter on A4 and a strip of white is left down the side.

A4	210 × 297 mm	8.27 × 11.69 in	ISO 216 — the rest of the world
Letter	215.9 × 279.4 mm	8.5 × 11 in	ANSI A — US, Canada, Mexico

Letter vs Legal vs Tabloid

Short answer: Letter and Legal are the same width — Legal is simply 76 mm longer, which is why contracts use it. Tabloid is a different thing entirely: exactly two Letter sheets side by side.

Letter	215.9 × 279.4 mm	8.5 × 11 in	Everyday documents
Legal	215.9 × 355.6 mm	8.5 × 14 in	Contracts, deeds, court filings
Tabloid / Ledger	279.4 × 431.8 mm	11 × 17 in	Spreadsheets, newspapers, small posters

Tabloid vs Ledger — is there a difference?

Short answer: Same sheet, different orientation. An 11 × 17 in sheet held upright is called Tabloid; turned on its side it is called Ledger. Some software and printer drivers keep the distinction; most people use the words interchangeably.

Tabloid	279.4 × 431.8 mm	11 × 17 in	Portrait orientation
Ledger	431.8 × 279.4 mm	17 × 11 in	Landscape orientation

Is A3 the same as Legal?

Short answer: No, and they are not even close. A3 is 81 mm wider and 64 mm longer than Legal. If a form asks for Legal, A3 will not do. The nearest North American size to A3 is Tabloid at 11 × 17 in, which is still about 18 mm narrower and 12 mm longer.

A3	297 × 420 mm	11.69 × 16.54 in	ISO 216
Legal	215.9 × 355.6 mm	8.5 × 14 in	Much narrower and shorter
Tabloid	279.4 × 431.8 mm	11 × 17 in	The closest US match to A3

A3 vs A4 — how much bigger?

Short answer: Exactly twice the area. A3 is an A4 unfolded along its long edge, so two A4 sheets side by side make one A3. The proportions are identical, which is why scaling between them never distorts a layout.

A4	210 × 297 mm	8.27 × 11.69 in	1 sheet
A3	297 × 420 mm	11.69 × 16.54 in	2 × A4
A2	420 × 594 mm	16.54 × 23.39 in	4 × A4

11 × 17 (Tabloid) vs A3

Short answer: Close, but not the same. A3 is 17.6 mm wider and Tabloid 11.8 mm taller, and the proportions differ (1:1.414 against 1:1.545), so one always leaves a white strip or crops when printed on the other. Of the North American sizes, Tabloid is still the nearest match to A3.

A3	297 × 420 mm	11.69 × 16.54 in	ISO 216
Tabloid	279.4 × 431.8 mm	11 × 17 in	ANSI B

Half Letter vs A5

Short answer: Each is half of its region's everyday sheet, and they are nearly the same size: A5 is 8.3 mm wider, Half Letter 5.9 mm taller. A page designed for one will be cropped or shifted slightly on the other.

A5	148 × 210 mm	5.83 × 8.27 in	Half of A4
Half Letter	139.7 × 215.9 mm	5.5 × 8.5 in	Half of Letter

B5 vs A4 — and ISO B5 vs JIS B5

Short answer: B5 sits between A5 and A4: ISO B5 is 34 mm narrower and 47 mm shorter than A4, with about 70% of its area. Japan's JIS B5 is a little larger again at 182 × 257 mm, so check which one a template means before printing.

A4	210 × 297 mm	8.27 × 11.69 in	ISO 216
JIS B5	182 × 257 mm	7.17 × 10.12 in	JIS P 0138
ISO B5	176 × 250 mm	6.93 × 9.84 in	ISO 216
A5	148 × 210 mm	5.83 × 8.27 in	ISO 216

Is 4 × 6 the same as A6? Is 5 × 7 the same as A5?

Short answer: No. A 4 × 6 in print has almost the same area as A6 but a different shape — 3.4 mm narrower and 4.4 mm taller, a 2:3 ratio instead of 1:√2. A 5 × 7 in print is much smaller than A5: 21 mm narrower and 32 mm shorter.

4 × 6 in	101.6 × 152.4 mm	4 × 6 in	Photo print, 2:3
A6	105 × 148 mm	4.13 × 5.83 in	ISO 216
5 × 7 in	127 × 177.8 mm	5 × 7 in	Photo print
A5	148 × 210 mm	5.83 × 8.27 in	ISO 216

Executive vs Letter vs A4

Short answer: Executive is the smallest of the three: about 32 mm narrower and 13 mm shorter than Letter, and 26 mm narrower and 30 mm shorter than A4. It survives mainly as a printer-driver preset; ISO-based references suggest B5 as its closest replacement.

Executive	184.2 × 266.7 mm	7.25 × 10.5 in	Printer-driver preset
Letter	215.9 × 279.4 mm	8.5 × 11 in	ANSI A
A4	210 × 297 mm	8.27 × 11.69 in	ISO 216

Paper weight (gsm) — what each number feels like

GSM is the weight in grams of one square metre of the paper. It is not exactly the same as thickness — a textured sheet feels thicker at the same gsm — but it is the number every print shop quotes, so it is worth recognising.

Weight	US equivalent	Type	Typical uses	How it feels
35–55 gsm	24–37 lb text	Newsprint	Newspapers, packing paper, throwaway inserts	Thin and slightly translucent — print shows through
70–90 gsm	47–60 lb text	Copy / office paper	Everyday printing, photocopies, internal documents	80 gsm is the global office default — light, flexible
100–120 gsm	67–80 lb text	Letterhead / premium document	Company letterhead, CVs, certificates, contracts	Noticeably more substantial in the hand, no show-through
130–170 gsm	88–115 lb text	Flyer / magazine stock	Flyers, leaflets, magazine pages, posters	Holds its shape when held up; usually gloss or silk coated
200–250 gsm	74–92 lb cover	Cover / brochure stock	Brochure covers, menus, folders, premium flyers	Card-like. This is where paper starts feeling expensive
300–350 gsm	110–130 lb cover	Business card / postcard stock	Business cards, postcards, invitations, tags	Rigid. 350 gsm is the usual business-card standard
400–600 gsm	150–220 lb cover	Premium / luxury board	Luxury business cards, packaging, art prints	Very stiff, often duplexed from two sheets

Rule of thumb: under 100 gsm is everyday paper, 100–200 gsm is quality print, above 200 gsm is card. A US "80 lb cover" and "80 lb text" are completely different weights — always confirm which scale a supplier means.

The five most-used sizes, in detail

Size	Size (mm)	Size (cm)	Size (in)	Common Uses
A3	297 × 420 mm	29.7 × 42 cm	11.69 × 16.54 in	Architectural drawings, large posters, tabloid spreads
A4	210 × 297 mm	21 × 29.7 cm	8.27 × 11.69 in	Everyday documents, letters, reports, forms (international standard)
A5	148 × 210 mm	14.8 × 21 cm	5.83 × 8.27 in	Notebooks, flyers, booklets, greeting cards
US Letter	215.9 × 279.4 mm	21.59 × 27.94 cm	8.5 × 11 in	Everyday US/Canada documents, forms, printouts
US Legal	215.9 × 355.6 mm	21.59 × 35.56 cm	8.5 × 14 in	Contracts and legal documents (US)

All dimensions are the official ISO 216 (A-series) and ANSI/US paper standards — the exact same values used internally by this site's own Math Worksheet, Handwriting Practice, and PDF tools, not rounded estimates.

A3

A3 is exactly double the area of A4 — the ISO 216 series is built so each size folds exactly in half to make the next size down. It's the standard choice for architectural and engineering drawings, large posters, and tabloid-style spreads.

✓Large enough for detailed drawings and posters
✓Exactly 2× the area of A4 — same aspect ratio, easy to scale
✓Standard size for printers with an A3 tray

✕Too large for standard printers without an A3 tray
✕Awkward to store or mail without folding
✕Overkill for regular text documents

A4

A4 is the international standard for everyday documents — letters, reports, forms, invoices — used in nearly every country except the US, Canada, and a handful of others that use US Letter instead.

✓Universal standard outside North America
✓Good balance of size and portability
✓Matches most templates and print shop defaults worldwide

✕Not the US/Canada standard (Letter is slightly different)
✕Narrower and taller than Letter, so shared PDFs don't perfectly fit both

A5

A5 is exactly half of A4 — the size of a typical notebook, greeting card, or flyer. It's popular for booklets, zines, and anything meant to be compact and handheld.

✓Compact and handheld — ideal for notebooks, flyers, booklets
✓Two A5 pages fit exactly on one A4 sheet for cheap printing
✓Cheaper to print and mail than A4

✕Too small for dense text or detailed tables
✕Not a standard size for business documents
✕Fewer printer/software presets support it directly

US Letter

Letter (8.5" × 11") is the standard paper size in the United States, Canada, and a few other countries — used for virtually all everyday documents, forms, and printouts there.

✓Standard size across the US and Canada
✓Wider than A4, giving slightly more horizontal margin
✓Default paper size for most US-made software and printers

✕Not the international (ISO 216) standard used by most of the world
✕Documents formatted for A4 can lose margin or get slightly cropped when printed as Letter

US Legal

Legal (8.5" × 14") is the same width as Letter but 3 inches taller — used mainly in the US for contracts, legal documents, and anything needing extra length for clauses or signatures.

✓Extra vertical space for contracts and multi-clause documents
✓Same width as Letter, so it fits standard binders and folders

✕Doesn't fit standard envelopes or most printer trays without adjustment
✕Rarely used outside the US legal/government context
✕Not supported by many international print shops

Frequently Asked Questions

What's the actual difference between A4 and US Letter?

A4 (210 × 297mm) is narrower and taller than Letter (215.9 × 279.4mm) — Letter is about 6mm wider and 18mm shorter. The difference is small but real: a PDF formatted for one can get its margins slightly cropped or shifted when printed on the other. To fit a whole A4 page onto Letter paper, scale it to about 94%; to fit a Letter page onto A4, about 97%.

Is A3 exactly double the size of A4?

Yes — that's the defining feature of the ISO 216 (A-series) system: each size, folded exactly in half along its long edge, produces the next size down with the identical aspect ratio. A3 folded in half is A4; A4 folded in half is A5, and so on.

Which paper size should I use for printable worksheets?

It depends on your country: A4 almost everywhere outside North America, US Letter in the US and Canada. Our Math Worksheet and Handwriting Practice generators let you pick either (plus A3/A5/Legal) so the PDF prints correctly on your local paper.

What is US Legal size actually used for?

Mainly contracts and legal documents in the United States — it's the same width as Letter but 3 inches (76mm) taller, giving extra room for clauses and signature blocks. It's rarely used outside the US legal/government context.

Can I convert a document from one paper size to another without losing content?

Usually with some margin adjustment, not a perfect 1:1 fit — A4 and Letter have different aspect ratios (not just different sizes), so content laid out for one will either get extra white space or a slightly cropped edge on the other. Content designed to scale (like our worksheet tools) handles this automatically; fixed pixel-perfect layouts often need manual re-checking.

What are the names of the paper sizes?

Outside North America they are named by series and number: A0 to A10 for general use, B0 to B10 for the sizes in between, and the C series for envelopes. North America names them by purpose instead — Letter, Legal, Tabloid, Executive — or simply by their measurement in inches, such as 11 × 17. Both systems appear in full on this page.

What is a quarter-page paper size?

A6, which is 105 × 148 mm. Fold an A4 in half and you get A5; fold it again and you get A6, a quarter of the original sheet. The North American near-equivalent is 4.25 × 5.5 in, a quarter of a Letter sheet.

What size is half an A4?

A5, 148 × 210 mm. Because every ISO 216 sheet has a 1:√2 ratio, folding across the long edge always produces the next size down exactly, with nothing trimmed off.

What is 18 × 24 inch paper called?

ARCH C in the architectural series, 457 × 610 mm. It is one of the most common poster and art-print sizes in North America. The next size up, 24 × 36 in, is ARCH D.

Is A3 legal size paper?

No. Legal is 215.9 × 355.6 mm (8.5 × 14 in) while A3 is 297 × 420 mm, so A3 is 81 mm wider and 64 mm longer. The closest North American size to A3 is Tabloid at 11 × 17 in.

What size is office paper?

A4, 210 × 297 mm, in every country that follows ISO 216 — which is everywhere except the United States, Canada and parts of Latin America, where the office default is Letter at 8.5 × 11 in.

What is A3 used for?

Spreadsheets and tables too wide for A4, technical drawings, menus, small posters, presentation handouts and children's artwork. It is the largest size most office printers can handle, which is why it is the usual step up from A4.

What is 11 × 17 paper called?

Tabloid when held upright and Ledger when turned sideways; in the ANSI engineering series the same sheet is called ANSI B. It measures 279.4 × 431.8 mm, close to A3 (297 × 420 mm) but a different shape.

Is 4 × 6 paper the same as A6?

No, although it is close. A 4 × 6 in sheet is 101.6 × 152.4 mm and A6 is 105 × 148 mm, so the areas are nearly equal but the shapes differ: 4 × 6 has a 2:3 ratio, A6 the ISO ratio of 1:√2. A photo sized for one will be cropped slightly on the other.

What size is B5 paper?

ISO B5 is 176 × 250 mm (6.93 × 9.84 in), between A5 and A4. Japan's JIS B5 is slightly larger at 182 × 257 mm, and printer settings list the two separately.

What size is Executive paper?

In printer drivers Executive is 7.25 × 10.5 in, or 184.2 × 266.7 mm. Some older references give 7.5 × 10 in (190 × 254 mm) instead, so check the exact dimensions your printer or template uses.

Is Half Letter the same as A5?

No, but they are close. Half Letter, also called Statement, is 5.5 × 8.5 in (139.7 × 215.9 mm) while A5 is 148 × 210 mm, so A5 is 8.3 mm wider and Half Letter 5.9 mm taller.

How are A paper sizes calculated?

ISO 216 starts from A0, a sheet with an area of one square metre and sides in the ratio 1:√2, which works out to 841 × 1189 mm. Each following size halves the previous one across its longer side, with dimensions rounded down to whole millimetres. Because the ratio never changes, A4 is exactly one sixteenth of A0 and scaling between sizes never distorts a layout.

What is 3 × 5 paper called?

It has no letter name — it is simply the 3 × 5 in index card, 76.2 × 127 mm. It is used for index cards, recipe cards and short notes.

Sources

ISO and ASME standards are sold rather than published free, so every dimension here was cross-checked against the references below. Inch sizes are converted at exactly 25.4 mm per inch.

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