Resources: Envelope Size Chart

Social Envelopes

Announcement envelopes, are also called A-style envelopes.
They are ideal for stationery, cards, invitations, photographs, greeting cards, small booklets, etc.

TYPE	SIZE	Suggested Enclosure
A-2	4.375" x 5.75"	4.25" x 5.5"(post cards, note cards)
A-6	4.75" x 6.5"	4.625" x 6.25" (notes, 4"x6" photos)
A-7	5.25" x 7.25"	5.125" x 7" (5x7"photo cards, invitations )
A-8	5.5" x 8.125"	5.375" x 7.875" (5x8" cards & invitations)
A-9	5.75" x 8.75"	5.5" x 8.5" (greeting cards)
A-10	6" x 9.5"	5.875" x 9.25" (invitations, panel cards)

Business Envelopes for Office or Personal Correspondence

In the US, the popular business envelope is the standard #10 Envelope.
It has become popular for both commercial and social designs.
The #10 envelope can hold a tri-fold letterhead or brochure, a 3UP certificate or card

Business Envelope Sizes

Name	Size in inches	Size in millimeters	Suggested Enclosure
No. 6¼	3 1/2 in x 6 in (3.5" x 6")	89 x 152 mm	3.25" x 5.75"
No. 6¾	3 5/8 in x 6 1/2 in (3.625" x 6.5")	92 x 165 mm	3.5" x 6.25"
No. 8	3 7/8 in x 7 1/2 in (3.875" x 7.5")	98 x 190 mm	3.75" x 7.25"
No. 9	3 7/8 in x 8 7/8 in (3.875" x 8.875")	98 x 225 mm	3.75" x 8.625"
No. 10	4 1/8 in x 9 1/2in (4.125" x 9.5")	105 x 241 mm	4" x 9.25"
No. 11	4 1/2 in x 10 3/8 in (4.5" x 10.375")	114 x 263 mm	4.25" x 10.125"
No. 12	4 3/4 in x 11 in (4.75" x 11")	120 x 279 mm	4.5" x 10.75"
No. 14	5 in x 11 1/2 in (5" x 11.5")	127 x 292 mm	4.75" x 11.25"