Change the DPI of an image
Set the DPI stored in a JPG, PNG or WebP without changing any pixels, or make the picture an exact print size at the DPI you choose.
Files never leave your device
Choose one or more JPG, PNG or WebP pictures.
DPI does not change quality. A picture is a grid of pixels. DPI only says how many of those pixels are printed per inch. The same 3000 × 2000 pixel photo is just as sharp at 72 DPI as at 300 DPI. It only becomes a bigger or smaller print. Forms that ask for "300 DPI" usually want that number stored in the file, and often a size in pixels too.
DPI
Need a different number of pixels, not just a different DPI? Use Resize Image. For passport and visa photos, use the Passport Photo Maker.
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How to use it
- Step 1: Tap the box and choose one or more JPG, PNG or WebP pictures. Their pixels and DPI are shown.
- Step 2: Choose a DPI such as 300, then choose to change only the DPI number, or to make a print size such as 3.5 x 4.5 cm.
- Step 3: Tap Change the DPI and download the pictures.
Your files never leave your device
This tool runs entirely in your browser. Nothing is uploaded to a server, so your documents and photos stay private. It is free, has no watermark and needs no sign-up.
Frequently asked questions
Does a higher DPI make the picture sharper?
No. DPI only says how many pixels are printed per inch. A 3000 x 2000 pixel photo has the same detail at 72 DPI and at 300 DPI. It only changes how large the picture prints. To get more detail you need a better photo, not a different DPI.
Are the pixels really untouched when I change only the DPI?
Yes. The compressed picture data is copied byte for byte, and only the small header that stores the DPI is rewritten. Our tests check this on JPG, PNG and WebP files.
Why does a form ask for 300 DPI?
Many forms and printers use the DPI stored in the file as a hint for the print size. Often they also ask for a size in pixels or centimetres. If so, use "Make it a print size", which resizes the picture to that size at the DPI you choose.
Which files work?
JPG, PNG and static WebP. Animated WebP, GIF and iPhone HEIC photos are not supported here. For HEIC, change it to JPG first with HEIC to JPG.
What does "make it a print size" do?
You type a width and a height, for example 3.5 x 4.5 cm. The picture is resized to the right number of pixels for the DPI you chose (413 x 531 pixels at 300 DPI) and the DPI is stored in the file. This changes the pixels, so the original is kept untouched and you get a new file.
Are my pictures uploaded?
No. Everything happens in your browser, on your device.
Read the guide: How to Change a Photo to 300 DPI for a Form →