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Image DPI converter

Check the print density saved inside a JPEG or PNG. Set a new DPI value while keeping the encoded image pixels unchanged, and see the resulting print dimensions.

Your image and captions are processed on this device and never uploaded. We do not see, store or log your files.

How it works

  1. Choose a JPEG or PNG file and wait for its pixel size and supported density fields to appear.
  2. Read any density conflict warning. Changing DPI reconciles every supported density field.
  3. Choose 72, 150, 300 or 600 DPI, or type a whole number from 1 to 65535.
  4. Check the print dimensions, choose Change image DPI and download the new file.

DPI changes print size, not detail

A 3000 × 2000 image at 300 DPI prints at 10 × 6.67 inches, or 25.4 × 16.93 cm. At 150 DPI it prints twice as wide and high. Changing density metadata does not add pixels, sharpen a photo or meet every printer requirement.

Consistent JPEG and PNG metadata

JPEG files can store JFIF density and EXIF XResolution, YResolution and ResolutionUnit. PNG can store pHYs density and eXIf fields. Supported values are reconciled to the chosen density. PNG stores whole pixels per meter, so the displayed DPI can differ slightly from the requested value.

Missing, conflicting and unsupported values

An image without density receives a new JFIF or pHYs field. Conflicting supported values are displayed before you change them. Unsupported TIFF/EXIF density layouts, ambiguous references and corrupt chunk CRCs are refused rather than partly rewritten. The encoded JPEG scan or PNG image data remains unchanged.

Metadata privacy

This tool preserves the rest of your metadata to avoid changing encoded image data. Existing camera location and capture information may remain in the download. It processes one image at a time and never uploads it.

Frequently asked questions

Does converting to 300 DPI improve image quality?

No. DPI describes print density. A low-resolution image retains the same pixels and detail after this edit.

What if two density fields disagree?

The checker displays the supported values and a warning. A successful change rewrites those values consistently. Unsupported metadata layouts are refused.

Does it resize or recompress my photo?

No. This metadata edit preserves the encoded JPEG scan and PNG image data. Use Resize image when you want different pixel dimensions.

Last reviewed: October 11, 2026

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