Reference library
C2 Envelope Paper Size
C2 measures 458 x 648 mm, 45.8 x 64.8 cm, or 18.03 x 25.51 in. See pixel dimensions by DPI, aspect ratio, bleed setup, comparisons, and related tools.
Last checked: 2026-05-01
How we calculate this
Methodology and source handling
We convert physical sizes to inches, multiply by the selected DPI/PPI value, and round to whole pixels.
Quick answer
Copy-ready answer
C2 is 458 x 648 mm, 45.8 x 64.8 cm, or 18.03 x 25.51 in. At 300 DPI, C2 is 5409 x 7654 px.
Dimensions and specs
| Millimeters | 458 x 648 mm | |
|---|---|---|
| Centimeters | 45.8 x 64.8 cm | |
| Inches | 18.03 x 25.51 in | |
| 300 DPI pixels | 5409 x 7654 px | |
| Aspect ratio | 1:1.4148 | |
| Standard family | ISO C Envelope Series |
Pixels
Pixel dimensions by DPI
| DPI / PPI | Width | Height | Use |
|---|---|---|---|
| 72 DPI | 1298 px | 1837 px | Screen or draft reference density |
| 96 DPI | 1731 px | 2449 px | Screen or draft reference density |
| 150 DPI | 2705 px | 3827 px | Screen or draft reference density |
| 300 DPI | 5409 px | 7654 px | Common high-quality print setup |
| 600 DPI | 10819 px | 15307 px | High-resolution archival or print workflow |
Formula
How to calculate this size
458 mm x 300 PPI = 5,409 px wide.
Use this when the artwork stops at the finished edge.
Add 0 mm per side before calculating pixels when artwork reaches the edge.
Common mistakes
Avoid these c2 envelope paper size problems
A paper size needs a PPI target before pixels mean anything for print.
Portrait and landscape use the same dimensions, but width and height swap in the export.
Paper pages show trim size first; add bleed only when the design prints to the edge.
Calculator
Calculate pixels and bleed
Enter any DPI to calculate the pixel dimensions for this physical size.
Compare
Compare C2 Envelope Paper Size
Open a curated comparison or send both sizes into the compare tool with a fragment URL.
- C2 Envelope Paper Size
- 458 x 648 mm
- C1
- 648 x 917 mm
- C2 Envelope Paper Size
- 458 x 648 mm
- C3
- 324 x 458 mm
- C2 Envelope Paper Size
- 458 x 648 mm
- A4
- 210 x 297 mm
- C2 Envelope Paper Size
- 458 x 648 mm
- US Letter
- 215.9 x 279.4 mm
Workflow
Use C2 Envelope Paper Size in a finished file
Copy the millimeter, centimeter, or inch dimensions for the selected paper standard.
Use 300 PPI for most sharp print exports, or match the printer requirement.
Multiply inches by PPI, then add bleed only when artwork reaches the trimmed edge.
Related
Related pages and tools
Same branch
Nearby pages
FAQ
Common questions
What is the exact C2 size?
C2 measures 458 x 648 mm, 45.8 x 64.8 cm, or approximately 18.03 x 25.51 in.
What is C2 in pixels at 300 DPI?
C2 at 300 DPI is 5409 x 7654 px when rounded to the nearest whole pixel.
What aspect ratio is C2?
C2 has an aspect ratio of about 1:1.4148 based on its 458 x 648 mm physical dimensions.
Should I add bleed to a C2 design?
Envelope print workflows vary by provider and production method. Confirm bleed, flap, and safe-area requirements with the printer or envelope template before output.
References
Sources and references
ISO 269 physical dimensions. Pixel values are calculated from millimeters / 25.4 x DPI and rounded to whole pixels.
-
ISO 269:1985
Used for ISO C envelope dimensions and DL envelope references.
-
HP paper size reference
Used as a reputable printer reference for North American office, ANSI, and envelope dimensions.
-
W3C CSS Values and Units Module
Used for CSS unit definitions, absolute unit relationships, and CSS px behavior.
Last checked: 2026-05-01