Reference library

C7 Envelope Paper Size

C7 measures 81 x 114 mm, 8.1 x 11.4 cm, or 3.19 x 4.49 in. See pixel dimensions by DPI, aspect ratio, bleed setup, comparisons, and related tools.

Last checked: 2026-05-01

See quick answer Compare sizes

At a glance

C7 is 81 x 114 mm, 8.1 x 11.4 cm, or 3.19 x 4.49 in. At 300 DPI, C7 is 957 x 1346 px.

Last checked: 2026-05-01 Source: ISO 269:1985 Found a spec change? Send correction.

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.

Methodology Editorial policy

Quick answer

Copy-ready answer

C7 is 81 x 114 mm, 8.1 x 11.4 cm, or 3.19 x 4.49 in. At 300 DPI, C7 is 957 x 1346 px.

81 x 114 mm

Dimensions and specs

Millimeters	81 x 114 mm
Centimeters	8.1 x 11.4 cm
Inches	3.19 x 4.49 in
300 DPI pixels	957 x 1346 px
Aspect ratio	1:1.4074
Standard family	ISO C Envelope Series

Pixels

Pixel dimensions by DPI

DPI / PPI	Width	Height	Use
72 DPI	230 px	323 px	Screen or draft reference density
96 DPI	306 px	431 px	Screen or draft reference density
150 DPI	478 px	673 px	Screen or draft reference density
300 DPI	957 px	1346 px	Common high-quality print setup
600 DPI	1913 px	2693 px	High-resolution archival or print workflow

Formula

How to calculate this size

Pixel formulapixels = millimeters / 25.4 x PPI

81 mm x 300 PPI = 957 px wide.

Trim result957 x 1,346 px

Use this when the artwork stops at the finished edge.

Bleed result957 x 1,346 px

Add 0 mm per side before calculating pixels when artwork reaches the edge.

Common mistakes

Avoid these c7 envelope paper size problems

Mixing screen pixels with print quality

A paper size needs a PPI target before pixels mean anything for print.

Forgetting orientation

Portrait and landscape use the same dimensions, but width and height swap in the export.

Adding bleed to a paper reference

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 C7 Envelope Paper Size

Open a curated comparison or send both sizes into the compare tool with a fragment URL.

compare tool C7 vs C6

C7 Envelope Paper Size: 81 x 114 mm
C6: 114 x 162 mm

50% smaller than C6 Envelope Paper Size. 0.0068 decimal ratio difference compare tool C7 vs C8

C7 Envelope Paper Size: 81 x 114 mm
C8: 57 x 81 mm

100% larger than C8 Envelope Paper Size. 0.0068 decimal ratio difference compare tool C7 vs A4

C7 Envelope Paper Size: 81 x 114 mm
A4: 210 x 297 mm

85.2% smaller than A4 Paper Size in Pixels, Millimeters, Centimeters and Inches. 0.0035 decimal ratio difference compare tool C7 vs US Letter

C7 Envelope Paper Size: 81 x 114 mm
US Letter: 215.9 x 279.4 mm

84.7% smaller than US Letter Paper Size. 0.0622 decimal ratio difference

C7 belongs to the ISO C Envelope Series family. Use this reference for print setup, document layout, template sizing, pixel conversion, and comparisons with nearby paper sizes. Pixel dimensions are calculated from the physical size and selected DPI.

Workflow

Use C7 Envelope Paper Size in a finished file

Confirm the physical size

Copy the millimeter, centimeter, or inch dimensions for the selected paper standard.

Choose PPI

Use 300 PPI for most sharp print exports, or match the printer requirement.

Calculate pixels

Multiply inches by PPI, then add bleed only when artwork reaches the trimmed edge.

Related pages and tools

same series C6 paper size same series C8 paper size common alternative A4 paper size common alternative US Letter paper size comparison C7 vs C6 comparison C7 vs C8 tool DPI calculator tool Print bleed calculator tool Compare sizes tool

Same branch

Nearby pages

A4 Paper Size in Pixels, Millimeters, Centimeters and Inches A5 Paper Size Legal Paper Size US Letter Paper Size A0 Paper Size A1 Paper Size A10 Paper Size A2 Paper Size

FAQ

Common questions

What is the exact C7 size?

C7 measures 81 x 114 mm, 8.1 x 11.4 cm, or approximately 3.19 x 4.49 in.

What is C7 in pixels at 300 DPI?

C7 at 300 DPI is 957 x 1346 px when rounded to the nearest whole pixel.

What aspect ratio is C7?

C7 has an aspect ratio of about 1:1.4074 based on its 81 x 114 mm physical dimensions.

Should I add bleed to a C7 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