A9 Envelope (US) paper size
146.05 × 222.25 mm
5.75 × 8.75 inches · 14.61 × 22.23 cm · aspect ratio 1:1.52
A9 Envelope (US) size is 146.05 × 222.25 mm. Those are the A9 Envelope (US) dimensions a printer works to; the same sheet in centimetres, inches, points and pixels is below.
What A9 Envelope (US) is for
A9 Envelope (US) is 5¾ × 8¾ inches, or 146.05 × 222.25 mm. A large announcement envelope used for oversized cards and photographs. It will swallow a half-folded Letter sheet, though it is not cut for one — a No. 10 is the envelope for that.
A9 Envelope (US) dimensions in every unit
| Unit | Width | Height |
|---|---|---|
| Millimetres | 146.05 mm | 222.25 mm |
| Centimetres | 14.61 cm | 22.23 cm |
| Inches | 5.75 in | 8.75 in |
| Points (PostScript) | 414 pt | 630 pt |
A9 Envelope (US) in pixels
Pixel dimensions depend entirely on the resolution you are working at — there is no single "pixel size" for a sheet of paper. Every resolution, with file sizes and canvas setup →
| Resolution | Pixels | Use |
|---|---|---|
| 72 DPI | 414 × 630 | Screen preview only — far too coarse to print |
| 150 DPI | 863 × 1313 | Draft printing, internal documents |
| 300 DPI | 1725 × 2625 | The standard for commercial print |
| 600 DPI | 3450 × 5250 | Fine detail, line art, archival scanning |
Setting up a print document? Use 300 DPI and add 3 mm of bleed on every edge unless your printer specifies otherwise.
How A9 Envelope (US) relates to the rest of the series
At 146.05 × 222.25 mm (5.75 × 8.75 inches) the aspect ratio is 1:1.522. US envelopes are not a halving series: each size is cut to hold a particular sheet or card, so the numbers step irregularly and nothing scales cleanly to anything else.
Of the standard sheets on this site, the largest that goes in flat is Half Letter at 139.7 × 215.9 mm, with a few millimetres to spare on each edge.
Folded, the largest standard sheet it takes is a Letter sheet folded in half.
About A9 Envelope (US)
5.75 × 8.75 inches. A large US announcement envelope. Unrelated to ISO A9.
Other US envelope sizes sizes
| Size | Millimetres | Inches |
|---|---|---|
| Envelope No. 10 | 104.775 × 241.3 mm | 4.13 × 9.5 in |
| A7 Envelope (US) | 133.35 × 184.15 mm | 5.25 × 7.25 in |
| A1 Envelope (US) | 92.075 × 130.175 mm | 3.63 × 5.13 in |
| A2 Envelope (US) | 111.125 × 146.05 mm | 4.38 × 5.75 in |
| A6 Envelope (US) | 120.65 × 165.1 mm | 4.75 × 6.5 in |
| A8 Envelope (US) | 139.7 × 206.375 mm | 5.5 × 8.13 in |
| A10 Envelope (US) | 152.4 × 241.3 mm | 6 × 9.5 in |
| Envelope No. 6 3/4 | 92.075 × 165.1 mm | 3.63 × 6.5 in |
| Envelope No. 9 | 98.425 × 225.425 mm | 3.88 × 8.88 in |
| Envelope No. 11 | 114.3 × 263.525 mm | 4.5 × 10.38 in |
| Envelope No. 12 | 120.65 × 279.4 mm | 4.75 × 11 in |
| Envelope No. 14 | 127 × 292.1 mm | 5 × 11.5 in |
Frequently asked questions
What size is A9 Envelope (US) in mm?
146.05 × 222.25 mm.
What size is A9 Envelope (US) in inches?
5.75 × 8.75 inches.
What size is A9 Envelope (US) in pixels?
There is no single answer — it depends on resolution. At the print standard of 300 DPI it is 1725 × 2625 pixels; at 72 DPI it is only 414 × 630.