Change Image DPI

Free Online DPI Changer for Images

DPI (dots per inch) is a piece of metadata stored inside an image file that tells printers and some software how large the image should appear when printed, based on its pixel dimensions. It's a common requirement for stock photo submissions, print services, and design templates that ask for images at "300 DPI" — even though the pixel content of the file doesn't need to change at all. LovePDFImg's Change DPI tool updates this metadata directly.

For JPG files, the DPI is stored in the JFIF header near the start of the file; for PNG files, it's stored in a chunk called pHYs. This tool reads your image's existing header, updates (or adds) the relevant DPI fields, and recalculates any checksums needed for PNG chunks — all without touching the actual pixel data. The result is the same image, at the same pixel dimensions, with new resolution metadata. Everything happens locally in your browser.

How to Change an Image's DPI

1. 1Upload your imageDrag and drop a JPG or PNG file, or click to browse.
2. 2Choose a DPI valuePick a common value like 72, 96, 150, or 300, or enter a custom number.
3. 3Click "Apply DPI"The tool updates the image's header metadata with the new DPI value.
4. 4Download your imageThe pixel content is unchanged — only the DPI metadata is updated.

Frequently Asked Questions