A0 = 1189 x 841 mm (46.8 x 33.1 inches)
A1 =  841 x 594 mm (33.1 x 23.4 inches)
A2 =  594 x 420 mm (23.4 x 16.5 inches)
A3 =  420 x 297 mm (16.5 x 11.7 inches)

A4 =  297 x 210 mm (11.7 x 8.3 inches)
A5 = 210 x 148 mm (8.3 x 5.8 inches)
A6 = 148 x 105 mm (5.8 x 4.1 inches)
DL = 210 x 99 mm (8.3 x 3.9 inches)

16 x 20'' (406 x 508 mm approx)
13 x 18'' (330 x 503 mm approx)
10 x 15'' (254 x 381 mm approx)
9 x 13'' (228 x 330 mm approx)
8 x 10'' (203 x 254 mm approx)
7 x 9'' (177 x 228 mm approx)

Square Prints:
16 x 16'' (406 x 406 mm approx)
14 x 14'' (355 x 355 mm approx)
12 x 12'' (304 x 304 mm approx)
10 x 10'' (254 x 254 mm approx)
8 x 8'' (203 x 203 mm approx)

60 x 80 cm (23.5 x 31.5 inches approx)
50 x 70 cm (19.5 x 27.5 inches approx)

40 x 50 cm (15.5 x 19.5 inches approx)
30 x 40 cm (11.5 x 15.5 inches approx)