#10 Envelope Size

The #10 envelope is the standard US business envelope — 9.5 × 4.125 inches (241.3 × 104.8 mm). At 300 DPI it's 2850 × 1237 pixels. It holds a standard US Letter (8.5 × 11 in) page folded in thirds. Used for invoices, direct mail, official correspondence, and any professional mailing where a letter needs to be enclosed.

Specifications

Pixels2850 × 1237 px (at 300 DPI)
Millimetres241.3 × 104.8 mm
Centimetres24.1 × 10.5 cm
Inches9.5 × 4.125 in
Aspect ratio9.5:4.125
Colour modeCMYK
Bleed3 mm (0.125 in)
Safe zone12.7 mm (0.5 in) from trim edges; 50 mm from left for window placement

#10 Envelope in Pixels at Different DPI

The pixel count changes with DPI setting — choose the right one for your output.

DPIWidth (px)Height (px)
72684297
96912396
1501,425619
3002,8501,237

Design Tips

  • The address window on a #10 window envelope is positioned 1 in from the left and 0.5 in from the bottom — if using a window envelope, design the document inside so the address lands in that zone when folded.
  • For branded envelopes, the return address goes in the upper-left, and your logo should sit within the top 25 mm of the envelope height.
  • Custom printed #10 envelopes require CMYK and are typically printed flat then folded — design the flat artwork with fold and glue tab marks.
  • USPS barcode placement zone is the bottom 5/8 inch (15.9 mm) of the envelope — avoid placing any design elements in this area.

How to Make #10 Envelope Designs in Playyy

Three steps, no design software. Set the size once — from the size options or straight in your prompt — and every design comes out at 2,850 × 1,237 px.

  1. 1

    Open Playyy

    Playyy runs in your browser, so there's nothing to download. Sign in and you'll land on the Home page.

  2. 2

    Type your prompt and set the #10 Envelope size

    Describe what you want in the input box on the Home page, then set the size whichever way is quicker. Pick #10 Envelope from the size options right underneath — print, poster, and social formats are all in that list. Or just say it in your prompt, like "#10 Envelope at 2,850 × 1,237 px", and Playyy matches it. Either way you get 2,850 × 1,237 px at 300 DPI, with no converting from millimetres or inches.

  3. 3

    Create your #10 Envelope design and export it for print

    Playyy generates the design at the full 2,850 × 1,237 px — that's #10 Envelope at 300 DPI, the resolution commercial print expects. Allow 3 mm (0.125 in) of bleed and export a print-ready PDF. Colour mode: CMYK.

Create #10 Envelope designs with Playyy

Type a prompt, pick #10 Envelope from the size options underneath it, and export at 2850 × 1237 px — no design software needed.

Start designing free →

Frequently Asked Questions

What is #10 envelope size in inches?+

A #10 business envelope is 9.5 × 4.125 inches (241.3 × 104.8 mm). It's the standard US mailing envelope for business correspondence and direct mail. A US Letter page (8.5 × 11 in) folded in thirds fits inside.

What is #10 envelope size in mm?+

#10 envelope is 241.3 × 104.8 mm. The closest ISO equivalent is a C4 envelope (324 × 229 mm) for unfolded A4, or a DL envelope (220 × 110 mm) for A4 folded in thirds — DL is slightly smaller than #10.

What size is a #10 envelope?+

9.5 × 4.125 in (241.3 × 104.8 mm), the standard US business envelope. At 300 DPI that is 2850 × 1237 px. It holds an 8.5 × 11 in sheet folded in three, which is why it is the default for invoices, statements, and letters.

Where does the window go on a #10 envelope?+

The standard window is 4.5 × 1.125 in, positioned 0.875 in from the left edge and 0.5 in from the bottom. Align the recipient address block in your letter template to that window before printing a run, not after.

What is the clear zone on a #10 envelope?+

Postal services require the bottom 0.625 in across the full width to stay clear for the sorting barcode, plus a clear area around the address block. Keep artwork and branding above and to the left of those zones.

Related Sizes