| SIZE | DIMENSION |
|---|---|
| C10 | 1.1 × 1.57 in |
| C9 | 1.57 × 2.24 in |
| C8 | 2.24 × 3.19 in |
| C7 | 3.19 × 4.49 in |
| C6 | 4.49 × 6.38 in |
| C5 | 6.42 × 9.02 in |
| C4 | 9.02 × 12.76 in |
| C3 | 12.76 × 18.03 in |
| C2 | 18.03 × 25.51 in |
| C1 | 25.51 × 36.1 in |
| C0 | 36.1 × 51.06 in |
The C-series paper sizes are a set of paper sizes used in commercial and publishing printing. They are named after the C series of sizes defined in the ISO 216 international standard. The C-series paper sizes for letter size paper are: A, B, C, D, E, F, G, H, J, K, L, M, N, O, P, Q, R, S, T, U, V, X, Y, Z, AA, BB, CC, DD, EE, FF, GG, HH, JJ, KK, LL, MM, NN, PP, QQ, RR, SS, TT, UU, VV, WW, XX, and YY.
A C4 paper is a size of paper that is 297 mm by 420 mm. The C4 paper size is one of the most popular paper sizes in the world. The C-series paper sizes are small, letter-sized sheets of paper. The C0 size is the same as a small sheet of US letter paper, the C1 is slightly smaller than a sheet of US letter paper (it’s commonly used for envelopes), and C2 is slightly smaller still. The main difference between the three sizes is the location and size of the crop marks.
The aspect ratio of C-series paper sizes is 1:√2, and it applies to all paper sizes with the prefix C (i.e. C2, C3, C4, etc.). C-series paper is often used for digital printing, such as for brochures, leaflets, magazines, pamphlets and postcards and business cards, gift certificates, invoices. Paper sizes such as C6 and C7 are also commonly used for invitations and cards.
