Envelope Size Guide

How do you know what size envelope is right for your piece of paper?

These are some common envelope types in comparrison to and A4 piece of paper.

This is a C4 (324x229mm) size envelope, one of the most common envelopes. It can hold a sheet of unfolded A4 paper.

This is a C5 (229x162mm) size envelope. It can hold a piece of A4 paper folded in half once or a piece of unfolded A5.

This is a C6 (114x162mm) size envelope. It can hold a piece of A4 paper folded into quarters, an A5 piece of paper folded in half once or a piece of unfolded A6.

This is a DL (110x220mm) size envelope.it can hold a A4 piece of paper folded into thirds or an A5 piece of paper folded once, this style of envelope is most commonly used in buisness.

C-Series Envelopes

A certain set of envelope sizes in common use are called the C-series and designated C4, C3, etc. These are defined from ISO 216 and are the geometrical mean of the A and B size envelopes, therefore C4 is bigger than A4, but smaller than B4. (More infomation can be found about A & B paper sizes here)

The table below shows the size of C-series envelopes, along with the dimensions of them:

 

 

The C6/C5 envelope size was introduced as a replacement for the DL envelope (mainly to allow a little more tolerance for automatic enveloping machines), however it has never really caught on and most DL style envelopes still measure 110x220 mm.