What does the R in 4R mean?

It is a photo-lab size name, not a unit. Each R size maps to a fixed print in inches: 3R is 3.5 × 5, 4R is 4 × 6, 5R is 5 × 7 and 8R is 8 × 10.

Which print size is best for ID pictures?

4R is the usual choice: one sheet holds 6 2x2, 24 1x1 or 8 passport size pictures.

Is A4 a photo print size?

A4 (21 × 29.7 cm) is a paper size, not an R size, but it is often used to print many ID pictures at once.

4R, 5R, 3R Photo Size Chart (2R to 8R)

4R is 4 × 6 in (10.16 × 15.24 cm), 5R is 5 × 7 in, 3R is 3.5 × 5 in. Chart of 2R to 8R in inches, cm and pixels, plus ID pictures per print.

Size chart
Measure	4R	5R	3R	8R	2R
Centimeters (W × H)	10.16 × 15.24 cm	12.7 × 17.78 cm	8.89 × 12.7 cm	20.32 × 25.4 cm	6.35 × 8.89 cm
Millimeters	101.6 × 152.4 mm	127 × 177.8 mm	88.9 × 127 mm	203.2 × 254 mm	63.5 × 88.9 mm
Inches	4 × 6 in	5 × 7 in	3.5 × 5 in	8 × 10 in	2.5 × 3.5 in
Pixels at 300 dpi	1200 × 1800 px	1500 × 2100 px	1050 × 1500 px	2400 × 3000 px	750 × 1050 px

ID pictures per print, edge to edge
ID picture	4R	5R	3R	8R	2R
2x2	6	6	2	20	1
1x1	24	35	15	80	6
passport size	8	10	4	28	2

4R size: 4 × 6 in (10.16 × 15.24 cm)

A 4R photo is 4 × 6 in, which is 10.16 × 15.24 cm (101.6 × 152.4 mm), or 1200 × 1800 px at 300 dpi. One 4R print fits up to 6 2x2, 24 1x1 or 8 passport size pictures, edge to edge.

5R size: 5 × 7 in (12.7 × 17.78 cm)

A 5R photo is 5 × 7 in, which is 12.7 × 17.78 cm (127 × 177.8 mm), or 1500 × 2100 px at 300 dpi. One 5R print fits up to 6 2x2, 35 1x1 or 10 passport size pictures, edge to edge.

3R size: 3.5 × 5 in (8.89 × 12.7 cm)

A 3R photo is 3.5 × 5 in, which is 8.89 × 12.7 cm (88.9 × 127 mm), or 1050 × 1500 px at 300 dpi. One 3R print fits up to 2 2x2, 15 1x1 or 4 passport size pictures, edge to edge.

8R size: 8 × 10 in (20.32 × 25.4 cm)

A 8R photo is 8 × 10 in, which is 20.32 × 25.4 cm (203.2 × 254 mm), or 2400 × 3000 px at 300 dpi. One 8R print fits up to 20 2x2, 80 1x1 or 28 passport size pictures, edge to edge.

2R size: 2.5 × 3.5 in (6.35 × 8.89 cm)

A 2R photo is 2.5 × 3.5 in, which is 6.35 × 8.89 cm (63.5 × 88.9 mm), or 750 × 1050 px at 300 dpi. One 2R print fits up to 1 2x2, 6 1x1 or 2 passport size pictures, edge to edge.

R sizes follow the standard photo-lab inch sizes. Values are exact unit conversions (1 inch = 2.54 cm); print counts assume no gaps between copies.

FAQ

What does the R in 4R mean?: It is a photo-lab size name, not a unit. Each R size maps to a fixed print in inches: 3R is 3.5 × 5, 4R is 4 × 6, 5R is 5 × 7 and 8R is 8 × 10.
Which print size is best for ID pictures?: 4R is the usual choice: one sheet holds 6 2x2, 24 1x1 or 8 passport size pictures.
Is A4 a photo print size?: A4 (21 × 29.7 cm) is a paper size, not an R size, but it is often used to print many ID pictures at once.

Updated 2 Nov 2026