How to Choose Photo Paper Sizes: 3R, 4R, 5R, Letter & A4

Sep 24, 2026
How to Choose Photo Paper Sizes: 3R, 4R, 5R, Letter & A4 illustration

Printing multiple ID photos on one sheet only works if the paper size in the layout matches the paper in the printer. Drugstore kiosks, home printers, and photo labs use different naming systems. This guide explains what 3R, 4R, 5R, US Letter, and A4 mean — and how to pick them in our free Photo Sheet Maker.

Quick answer

If you print at…Choose this paper in the sheet maker
Most US / drugstore photo kiosks6 Inch (4R) — 15.2 × 10.2 cm
Smaller wallet / 5″ prints5 Inch (3R) — 12.7 × 8.9 cm
Home inkjet on US letter stockLetter — 21.59 × 27.94 cm
Home inkjet on metric paperA4 — 21 × 29.7 cm (or A5 / A6)
Canon 4×6 photo paper packsCanon 4×6 Photo Paper — 13.35 × 8.9 cm

Always print at 100% / actual size and turn off “fit to page” or auto-crop.

Need a compliant passport photo first? Start on the homepage maker, then lay out copies with the Photo Sheet Maker.

What “R” sizes mean (3R, 4R, 5R…)

The R series comes from traditional photo-lab paper. The number roughly tracks inches on the short side, but labs publish exact centimeters. Our tool uses the same numbers as common layout tools (including sandphoto-style specs):

NameAlso calledSize (cm)Size (in, approx.)Typical use
5 Inch (3R)3R12.7 × 8.9~5 × 3.5Small prints, wallets
6 Inch (4R)4R, “4×6”15.2 × 10.2~6 × 4Default drugstore sheet
7 Inch (5R)5R, “5×7”17.8 × 12.7~7 × 5Larger portrait sheets
8 Inch (6R)6R20.3 × 15.2~8 × 6Bigger lab sheets
10 Inch (8R)8R25.4 × 20.3~10 × 8Large photo paper
12 Inch25.4 × 30.48~10 × 12Oversized sheets

Tip: When a kiosk says “4×6”, pick 6 Inch (4R) in the sheet maker — not a random “close enough” size. A few millimeters off will make ID photos print too large or too small.

Office / ISO sizes (A3–A6, B3–B5)

These are standard office papers, useful if you print at home:

NameSize (cm)Notes
A610.5 × 14.8Postcard-ish; fewer copies
A514.8 × 21Half of A4
A421 × 29.7Common home/office printer
A329.7 × 42Large; many photos per sheet
B517.6 × 25Between A5 and A4
B425 × 35.3Large
B350 × 70.7Very large / specialty

Letter, postcard & specialty stocks

NameSize (cm)Notes
Letter21.59 × 27.94US letter (8.5×11 in)
Postcard14.8 × 10Generic postcard stock
Hagaki10 × 14.8Japanese postcard
Canon 4×6 Photo Paper13.35 × 8.9Matches many Canon 4×6 packs (slightly smaller than full 4R)

If your pack is branded “Canon 4×6”, prefer the Canon 4×6 option over generic 4R so margins stay correct.

How to print ID photos the right way

  1. Create or upload a ready ID photo

  2. Choose ID size + paper size
    Match the paper to the physical stock you will buy (4R for most kiosks).

  3. Set a small gap + cut-line color
    A few millimeters of gap and a blue border make scissors easier — same idea as classic sheet layout tools.

  4. Download JPEG at 300 DPI and print at 100%
    Disable fit-to-page. See pricing if you still need to unlock a clean passport photo.

FAQ

Is 4×6 the same as 4R?

In kiosk language, yes — “4×6” usually means 6 Inch (4R) paper (~15.2 × 10.2 cm). Always confirm the cm size if a brand is unusual (for example Canon packs).

Letter vs A4 — which should I use?

Use Letter for US letter paper and A4 for metric A4. They are close but not identical; mixing them shifts how many photos fit and how large each photo prints.

Can I put UK 35×45 photos on 4R paper?

Yes. Pick UK / EU Passport (35×45 mm) as the photo size and 6 Inch (4R) as the paper. The sheet maker keeps the photo upright and only rotates the paper if that fits more copies.

Ready to lay out your ID photos?

Use the free Photo Sheet Maker to tile a ready passport photo onto 4R, 5R, Letter, A4, and more — then print at 100%.