MM to Pixels for Photoshop

Convert millimeters to Photoshop pixels for print documents, image sizing, and export dimensions. The calculator starts at 300 DPI for print-ready work.

Photoshop Conversion Input

Real-time sync active
Photoshop quick values
mm
px

Photoshop Pixel Result

37.7953 px
10 mm = 37.7953 px @ 96 DPI

Conversion Formula

px = mm × (DPI ÷ 25.4)
px = 10 × (96 ÷ 25.4)
px = 10 × 3.7795
px = 37.7953

Photoshop document value

Centimeters
1 cm
Inches
0.3937 in
Points (pt)
28.3465 pt
CSS rem (16px base)
2.3622 rem

How MM to Pixels for Photoshop Calculator Works

To convert millimeters to Photoshop pixels, this calculator applies the same formula Photoshop uses internally in the Image Size and New Document dialogs: multiply the millimeter value by the document's PPI (Pixels Per Inch) divided by 25.4.

1

Enter the mm value

Type a millimeter value — for example, 210 mm for A4 width or 25.4 mm for one inch. The calculator accepts whole numbers and decimals, matching the precision Photoshop's Document Size fields support.

2

Select the DPI

Choose the PPI (Pixels Per Inch) your Photoshop document uses. For print-ready work, 300 PPI is the standard. For web export, 72 or 96 PPI is common. The calculator defaults to 300 PPI because most Photoshop-to-print workflows require it.

3

Read the pixel result

Read the pixel result. This is the exact Pixel Dimensions value Photoshop would display in the Image Size dialog when the Document Size is set to your millimeter value at your chosen PPI.

Photoshop links physical units (mm, cm, inches) to pixel dimensions through PPI. When you change PPI in Image Size with Resample checked, Photoshop recalculates pixel dimensions using this same formula. This calculator mirrors that logic so you can plan canvas sizes before opening Photoshop.

MM to Pixels for Photoshop Formula

The Photoshop mm to pixels formula is: pixels = mm × (PPI ÷ 25.4). Photoshop uses PPI (Pixels Per Inch) rather than DPI, though the math is identical.

px = mm × ( DPI ÷ 25.4 )

This mm to px formula has 3 variables:

  • mm — the physical dimension in millimeters, matching Photoshop's Document Size field
  • PPI — the resolution set in Image Size or New Document (e.g., 300 for print, 72 for legacy web)
  • 25.4 — millimeters per inch, the fixed conversion constant

MM to Pixels for Photoshop Formula Examples

A4 width at 300 PPI

px = 210 × (300 ÷ 25.4) px = 210 × 11.811 px = 2480.315

A4 height at 300 PPI

px = 297 × (300 ÷ 25.4) px = 297 × 11.811 px = 3507.874

1 inch at 72 PPI

px = 25.4 × (72 ÷ 25.4) px = 25.4 × 2.8346 px = 72

The reverse formula is: mm = px × (25.4 ÷ PPI). In Photoshop, this is what happens when you view Document Size in millimeters — Photoshop divides your Pixel Dimensions by the PPI factor. At 300 PPI, an A4 page (210 × 297 mm) equals 2480 × 3508 pixels, which is the standard resolution for high-quality print output.

MM to Pixels for Photoshop Conversion Chart

Reference table showing mm to pixel values at the 4 PPI settings Photoshop designers use most. Use this chart to plan canvas sizes, placed image dimensions, and export resolutions without opening Photoshop.

mm px @ 72 DPI px @ 96 DPI px @ 150 DPI px @ 300 DPI
0.5 1.4173 1.8898 2.9528 5.9055
1 2.8346 3.7795 5.9055 11.811
2 5.6693 7.5591 11.811 23.622
3 8.5039 11.3386 17.7165 35.4331
5 14.1732 18.8976 29.5276 59.0551
10 28.3465 37.7953 59.0551 118.1102
15 42.5197 56.6929 88.5827 177.1654
20 56.6929 75.5906 118.1102 236.2205
25 70.8661 94.4882 147.6378 295.2756
50 141.7323 188.9764 295.2756 590.5512
100 283.4646 377.9528 590.5512 1181.1024
210 595.2756 793.7008 1240.1575 2480.315
297 841.8898 1122.5197 1753.937 3507.874

At 300 PPI, an A4 page (210 × 297 mm) requires a 2480 × 3508 pixel canvas in Photoshop — the standard for commercial print. For web and social media export, 72 or 96 PPI produces smaller pixel counts suitable for screen display.