How to change image dpi
- Choose your image. Its current DPI shows under the file name if it has one.
- Pick the DPI you need, for example 300.
- Tap Change DPI and download the JPG.
What DPI really changes
DPI is a label inside the file that tells printers how many pixels to place per inch. Changing it does not add or remove pixels, so the image looks identical on screen. What changes is the printed size: a 1200 × 1800 px photo prints at 4 × 6 inches at 300 DPI, or 16.7 × 25 inches at 72 DPI.
Many online forms check this label and reject files that say 72 or 96 DPI. This tool rewrites only the label in JPG files, without re-compressing them. Other formats are converted to high-quality JPG first.
Need a specific print size?
If the form asks for both a DPI and a size in cm, use resize image in cm, which sets both at once.
Is it safe to upload my photo?
Your image is never uploaded. ResizeKB processes files inside your own browser using the same technology that draws images on web pages, so the photo never leaves your phone or computer. That matters for documents like passport photos, ID scans and signatures. You can even disconnect from the internet after the page loads and the tool keeps working.
Frequently asked questions
Does changing DPI improve quality?
No. Quality depends on the number of pixels. DPI only controls the printed size.
How do I check an image's DPI?
Choose it here; the current DPI appears next to the file size. On Windows you can also right-click the file, then Properties > Details.
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Last updated 2026-10-27