DPI Checker & Changer
Check and change image DPI free online.
How to use this tool
Upload an image
Drop a PNG or JPEG. We'll read its stored DPI and dimensions instantly.
Pick a new DPI
Choose 72, 150, 300 or type a custom value — we rewrite the file header.
Download
Get the updated file with the new DPI baked in. Same pixels, new metadata.
Frequently asked questions
Does changing DPI improve image quality?
No — and any tool that claims otherwise is misleading you. DPI is just a number stored in the file header telling printers how densely to place the existing pixels. Changing it never adds detail, sharpness or pixels.
Then why change DPI at all?
Print workflows. A 3000×2400 px image at 300 DPI prints at 10×8 inches; the same file at 72 DPI would try to print at 41×33 inches. Setting the right DPI makes the file behave correctly in InDesign, Photoshop and print shops.
Which formats are supported?
PNG (pHYs chunk) and JPEG (JFIF APP0 header). WebP, GIF, BMP and HEIC don't store DPI the same way, so they're not supported here — you'll get a friendly message instead of a broken file.
Is my image uploaded anywhere?
No. The file is read and rewritten entirely in your browser. Your image never leaves your device.
My PNG shows "DPI not set" — is that normal?
Yes. Many PNGs (screenshots, web exports) simply don't store resolution metadata. Setting a DPI here adds it.