Resize any image to exact millimeter dimensions in your browser. Set width and height in mm, lock the aspect ratio, optimize the file size to a target KB, and pick from popular presets, 35×45 passport, 50×70 print, A4, A6, and more. Output as JPG, PNG, or WebP at 200 DPI. No upload required.
Drag and drop or choose any image to resize.
Type the exact width and height in millimetres.
Click Resize and download the image at the exact MM dimensions.
Print designers, signage shops, and brochure layouts all measure in millimetres. The MM resizer takes the exact target dimensions and outputs an image at print-ready DPI for any media size.
Skips the unit-conversion math that always introduces a one or two pixel rounding error.
Set the exact width and height in millimeters with 0.1 mm precision. The pixel output is calculated at 200 DPI using the formula px = (mm / 25.4) × 200. Perfect for passport photos, ID photos, print layouts, and government application portals that require physical dimensions rather than pixel sizes.
Six built-in presets cover the most common print and photo sizes: 35×45 mm passport, 50×50 mm square, 50×70 mm photo, 100×150 mm 4×6 print, A6 landscape (148×105), and full A4 (210×297). One click sets both width and height. You can also enter custom values manually for any other size you need.
Toggle Optimize File Size and enter your target KB. The tool runs a binary search over JPEG quality (5%-95%) and re-encodes the image until the resulting file size is within 5 KB of your target. Useful for government portals that limit upload sizes to 20 KB, 50 KB, 100 KB, or other specific values.
Your image never leaves your device. The entire tool, file loading, resize, compression, runs in your browser using the HTML5 Canvas API. No file is sent to any server, no account is needed, and nothing is stored. The downloaded JPG, PNG, or WebP is generated entirely on your device.
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Common questions about resizing images in millimeters.
