ISO C series (envelopes)
C8 envelope size
C8 envelope measures 57 x 81 mm (2.24 x 3.19 in). Part of the ISO C series (envelopes).
57 x 81millimetres
2.24 x 3.19inches
673 x 957pixels @ 300 dpi
Dimensions in every unit
| Unit | Width x height |
|---|---|
| Millimetres | 57 x 81 mm |
| Centimetres | 5.7 x 8.1 cm |
| Inches (decimal) | 2.244 x 3.189 in |
| Inches (fraction) | 2 1/4 x 3 3/16 in |
| Points (1/72 in) | 161.6 x 229.6 pt |
| Picas | 13.46 x 19.13 pc |
Pixel dimensions by resolution
| Resolution | Pixels | Megapixels |
|---|---|---|
| 72 dpi | 162 x 230 px | 0 MP |
| 96 dpi | 215 x 306 px | 0.1 MP |
| 150 dpi | 337 x 478 px | 0.2 MP |
| 200 dpi | 449 x 638 px | 0.3 MP |
| 300 dpi | 673 x 957 px | 0.6 MP |
| 600 dpi | 1,346 x 1,913 px | 2.6 MP |
300 dpi is the usual target for printed photos and artwork; 72–96 dpi is screen resolution.
Document size with bleed
| Bleed | Millimetres | Inches |
|---|---|---|
| 3 mm bleed (each side) | 63 x 87 mm | 2.48 x 3.425 in |
| 0.125 in bleed (each side) | 63.4 x 87.4 mm | 2.494 x 3.439 in |
How many C8 envelope fit on a press sheet
| Sheet | Without bleed | With 3 mm bleed |
|---|---|---|
| A4 | 10-up | 9-up |
| A3 | 25-up | 18-up |
| SRA3 | 25-up | 25-up |
| Letter | 9-up | 9-up |
| Tabloid 11 x 17 in | 21-up | 18-up |
| 12 x 18 in | 25-up | 21-up |
| 13 x 19 in (Super B) | 32-up | 25-up |
| B2 (offset) | 72-up | 56-up |
| B1 (offset) | 144-up | 121-up |
Simple grid imposition with no gutters or gripper margin; real layouts may fit fewer.
The √2 system
C8 envelope has an aspect ratio of 1 : 1.4211 — close to √2 (1.4142). Folding or cutting it in half across the long side produces the next smaller size in the series with the same proportions, and two sheets side by side form the next larger size. This is why scaling between sizes in the series (for example on a photocopier) never crops or distorts the page.
Similar sizes
Frequently asked questions
What are the dimensions of C8 envelope?
C8 envelope is 57 x 81 mm, which is 2.24 x 3.19 in (2 1/4 x 3 3/16 in).
How many pixels is C8 envelope at 300 DPI?
673 x 957 pixels at 300 dpi, or 337 x 478 at 150 dpi.
Sources & data
- Dimensions per the relevant standard; see sources.