PX to MM Converter
Convert pixels to mm, cm and inches at any DPI to see how big an image will actually print, with paper size presets, bleed and safe margin — all calculated instantly in your browser.
Unit converter
Paper size
Bleed & safe margin
- Trim size210.00 × 297.00 mm · 2480 × 3508 px
- With bleed216.00 × 303.00 mm · 2551 × 3579 px
- Safe area204.00 × 291.00 mm · 2409 × 3437 px
Everything runs locally in your browser. Nothing is uploaded to any server — close the tab and your files are gone.
1000 px cheat sheet
How big a 1000 px wide image actually is once you pick a DPI:
| DPI | Millimeters (mm) |
|---|---|
| 72 | 352.78 mm |
| 96 | 264.58 mm |
| 150 | 169.33 mm |
| 300 | 84.67 mm |
| 600 | 42.33 mm |
Which DPI should I use?
- 72 DPI — legacy screen resolution (pre-Retina displays)
- 96 DPI — the CSS reference pixel used by browsers and UI design
- 150 DPI — draft-quality print, quick proofs
- 300 DPI — standard for print production (brochures, magazines)
- 600 DPI — fine art prints and large-format signage
How to use
Type your pixel size
Enter your image’s pixel width (or height) into the px row, and the mm, cm and inch rows update instantly.
Set the DPI you’ll print at
Pick a preset (72 / 96 / 150 / 300 / 600) or type a custom value. The same pixel count maps to a very different physical size depending on DPI.
Compare against a paper size
Select an ISO A or B size, US Letter, Legal or Tabloid, or a card/postcard preset to see whether your pixels cover the page at that DPI.
Check bleed and safe margin
If the image is headed to a print shop, set bleed and safe margin in mm to see the trim size, the size with bleed, and the safe area in both mm and px.
Frequently asked questions
How many mm is 1000 px at 300 DPI?
At 300 DPI, 1000 px is 84.67 mm (about 8.5 cm), from mm = px ÷ DPI × 25.4. At 72 DPI the same 1000 px works out to 352.78 mm — over four times larger — because a lower DPI spreads the same pixels across more physical space.
How big will my 3000 px image print at 300 DPI?
Exactly 254 mm, or 25.4 cm — 10 inches on the nose, since 3000 ÷ 300 = 10 in. At 72 DPI the same file would print at roughly 1058 mm (over a meter), which is why the DPI you set here matters as much as the pixel count.
Why does the same pixel count give a different mm size at another DPI?
A pixel has no fixed physical size on its own — it only gets one once you assign it a resolution. DPI says how many of those pixels are packed into each inch, so raising the DPI shrinks the printed size for the same px count, and lowering it enlarges the print.
Is a screen pixel the same physical size as a print pixel?
No. A screen pixel’s physical size depends on the display’s own PPI and varies from monitor to monitor, while a print pixel’s size is whatever DPI you export at. This tool lets you pick the DPI so you can see the physical size before you print, not the on-screen size.
What DPI should I use to convert px to mm for a print file?
300 DPI is the standard for most print production like brochures and magazines. Use 150 DPI for a quick draft proof, and reserve 600 DPI for fine art prints or large-format signage viewed up close.
Can I get the size in cm or inches instead of mm?
Yes — the mm, cm, in and px rows are all linked, so typing a value into the px row updates the cm and inch rows in the same instant, with no extra steps.