Change image DPI
Files never leave your deviceDrop a JPG or PNG and set its DPI to 300 or any value. Only the resolution field in the file changes; the pixels and the image quality stay exactly the same, and the page reads the DPI back from the saved file to prove it.
JPG and PNG keep every pixel: only the DPI field changes. Other formats are saved as JPG first. To change the pixel size for a print size, use the cm/inch resizer.
How to use it
- Pick the DPI you need: 300 for print and most forms, or 72, 96, 150, 200, 600, or a custom value.
- Drop JPG or PNG files. WebP, HEIC and AVIF are saved as a high-quality JPG first, because they have no standard DPI field.
- Check the before and after DPI and the print size on each result, then download.
Details
- JPG
- Writes the JFIF density and, when present, the EXIF XResolution/YResolution. Image data copied byte for byte
- PNG
- Writes the pHYs chunk (pixels per metre). Image data copied byte for byte
- Other formats
- WebP, HEIC, AVIF, GIF, BMP: converted to JPG at quality 95, then the DPI is set
- Check
- The DPI is read back from the output file before you download it
- Range
- 1 to 65,535 DPI
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.
Does changing DPI change the quality?
No. DPI is a number stored in the file that tells printers how many pixels to put in each inch. A 1200×1800 photo has the same pixels at 72 or 300 DPI; it just prints at 16.7×25 in or at 4×6 in.
A form says the photo must be 300 DPI. Is this enough?
If the form only reads the DPI field, yes. If it also asks for a size in cm or a pixel size, set both at once with Resize image in cm, which makes the pixel count match the print size at that DPI.
Why do some apps still show 72 or 96 DPI?
Some viewers ignore the field and always assume 72 or 96. Windows Properties, macOS Preview, Photoshop and GIMP read it. The page shows the value it read back from your saved file.
Can I increase DPI to make a blurry photo sharp?
No. A higher DPI number cannot add detail. It only makes the photo print smaller. To check how large a photo can print sharply, use the print size calculator.