Resize an image in cm, mm or inches
Forms and printers often give sizes in cm and DPI instead of pixels. Enter them directly — we do the maths and write the DPI into the file.
- 🔒 No upload
- ∞ No limits
- 🎯 Exact KB
- ✓ No sign-up
Drop images here or choose filesTap to choose images
🔒 Processed on your device — never uploaded · Free · No sign-up
Size, DPI, name & date on photo
Needed for cm/mm/inch sizes (default 200) and written into the file.
Examples: — always use the exact numbers in your form's instructions.
KB (if your form has a minimum)
Key facts
- Converts cm/mm/inches to pixels at your DPI (pixels = cm ÷ 2.54 × DPI).
- Writes the DPI into the JPG or PNG so print and form checks read the right physical size.
- Optional maximum KB at the same time.
- Runs locally — nothing is uploaded.
How to resize an image in cm, mm or inches
- Drop your image.
- Enter width and height, choose cm/mm/inch and the DPI.
- Download — the file has the exact size and DPI.
Quick reference at 200 DPI
| Physical size | Pixels at 200 DPI | Pixels at 300 DPI |
|---|---|---|
| 3.5 × 4.5 cm | 276 × 354 | 413 × 531 |
| 2 × 2 in | 400 × 400 | 600 × 600 |
| 3.5 × 1.5 cm | 276 × 118 | 413 × 177 |
Frequently asked questions
What DPI should I use?
Use the DPI stated in your form or by your printer. If none is stated, 200 DPI is common for online forms and 300 DPI for printing.
Is my photo uploaded anywhere?
No. The image is resized inside your browser and never leaves your device — important for ID photos and signatures.
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