FAQs > Office Supplies - Envelopes Size and Style Guide

Envelopes come is a variety of shapes, sizes and specifications which can seem bewildering at first. Below is our handy envelope size guide which should answer all your questions.

Sizes

The most common sizes used are normally those that can fit A4 paper inside either whole or by folding a certain number of time. These envelopes are named with a letter and a number e.g. C6.

C4 size 324 x 229mm or 12.75" x 9"
C4 envelopes hold an A4 sheet unfolded.

C5 size 229 x 162mm or 9" x 6.38"
C5 envelopes hold an A4 sheet folded once or an A5 sheet unfolded.

C6 size 114 x 162mm or 4.5" x 6.38"
C6 envelopes hold an A4 sheet folded twice or an A5 sheet folded once.

DL size 110 x 220mm or 4.5" x 8.67
DL envelopes hold an A4 sheet folded twice or an A5 sheet folded once.

Envelopes come in standardised sizes which lets you easily choose what is right for your needs.

Below is a table of the most common sizes.

Metric (mm)	Envelope Size	Imperial (inches)

98 x 67		3.86" x 2.67"
102 x 76		4" x 3"
110 x 220	DL	4.33" x 8.67"
114 x 162	C6	4.5" x 6.38"
125 x 89		4.88" x 3.5"
152 x 102		6" x 4"
190 x 127		7.5" x 5"
229 x 140		7.5" x 5.5"
229 x 102		9" x 4"
229 x 162	C5	9" x 6.38"
235 x 121		9.25" x 4.75"
240 x 165		9.5" x 6.5"
241 x 178		9.5" x 7"
254 x 178		10" x 7"
270 x 216		10.63" x 8.5"
292 x 241		11.5" x 9.5"
305 x 127		12" x 5"
305 x 250		12" x 10"
318 x 267		12.5" x 10.5"
324 x 229	C4	12.75" x 9"
330 x 279		13" x 11"
350 x 248		13.75" x 9.75"
353 x 229		14" x 9"
381 x 254		15" x 10"
381 x 151		15" x 6"
394 x 318		15.5" x 12.5"
406 x 305		16" x 12"
444 x 368		17.5" x 14.5"
457 x 324	C3	18" x 12.75"

Envelope Styles

Envelopes can come in a variety of styles and specifications.

Gummed - Moisten adhesive on flap and press to seal.
Press Seal - Simply fold flap against back of envelope and press to seal.
Peel and Seal - Remove Strip to reveal adhesive and press against back of the envelope.