# Resize image in cm, mm or inches

> Resize a photo or signature to an exact size in cm, mm or inches at 300, 200 or any DPI. Crop to fill or fit inside, and the DPI is written into the file.

URL: https://tools.cuelark.com/resize-image-in-cm
Publisher: Cuelark Team (https://cuelark.com)
Updated: 2026-11-10
Price: free, no sign-up
Privacy: runs in the browser; files are not uploaded

Type the size in centimetres, millimetres or inches and the DPI, and get an image with the exact pixel count for that print size. 3.5×4.5 cm at 300 DPI is 413×531 pixels. Resizing runs in your browser.

## How to use it

1. Choose cm, mm or inch and type the width and height. Leave one blank to keep the photo's proportions.
2. Pick the DPI the form or printer asks for (300 is the usual print value), and Crop to fill or Fit inside with a white border.
3. Drop the images. Check the pixel size and the physical size on each result, then download.

## Details

- **Formula:** pixels = size in inches × DPI (1 in = 2.54 cm = 25.4 mm), rounded to whole pixels
- **Examples:** 3.5×4.5 cm at 300 DPI = 413×531 px. 6×2 cm at 200 DPI = 472×157 px. 2×2 in at 300 DPI = 600×600 px
- **Fit:** Crop to fill (centre crop, no stretching) or Fit inside (whole image on a white background)
- **Output:** JPG (quality 92) or PNG, with the DPI stored in the file (JFIF/EXIF or PNG pHYs)
- **Limits:** No file count limit. Very large images (above ~16,000 px on a side, or ~250 megapixels on phones) can exceed the browser's canvas limit.

## Questions

### Are my files uploaded?

No. The page loads its code once, then reads and processes your files inside the browser tab. Nothing is sent to a server; you can confirm it in your browser's network panel while a file converts.

### How many pixels is 1 cm?

It depends on the DPI. At 300 DPI, 1 cm is about 118 pixels (300 ÷ 2.54). At 200 DPI it is about 79 pixels, and at 96 DPI about 38. This page does the conversion for you.

### Will enlarging a small image make it sharper?

No. If the size you ask for needs more pixels than the original has, the image is upscaled and looks softer when printed. The result line says when that happened. Use a larger original instead.

### Why does my photo viewer still show a different size in cm?

Most viewers show pixels, not centimetres. Apps that show a print size read the DPI field, which this page writes into the file, so Photoshop, GIMP and Windows Properties show the size you set.

### Can I resize a signature to 6×2 cm?

Yes. Type 6 and 2 in cm and pick the DPI on the form. If the form also has a KB limit, run the result through Compress signature to 20 KB, which keeps the pen stroke dark.

## Related tools

- [Change image DPI](https://tools.cuelark.com/change-image-dpi)
- [Print size and PPI calculator](https://tools.cuelark.com/print-size-calculator)
- [Passport size photo print sheet](https://tools.cuelark.com/photo-print-sheet)
- [Compress signature to 20 KB](https://tools.cuelark.com/compress-signature-to-20kb)

## Guides

- [Passport and visa photo sizes by country (official rules, with sources)](https://tools.cuelark.com/guides/passport-photo-size-by-country)