Supported JPEG unit=1 JFIF metadata, simple existing Exif resolution, and compatible sources that can be synchronized safely.
Metadata converter · 300 DPI
Convert an image to 300 DPI online
Set supported image resolution metadata to 300 DPI directly in your browser. The converter reads the file locally, checks its format and dimensions, and rewrites only safe metadata structures. It does not resample, add pixels, sharpen, or improve image quality. Downloaded output is checked by the tool before it is offered, and unsupported or ambiguous files are refused instead of being rewritten.
Private browser tool
Set image metadata to 300 DPI
No upload
Your image stays in your browser. Image bytes, filename, and Exif metadata are not uploaded. Privacy details.
Up to 25 MB and 50 megapixels. You can also paste an image.
Choose an image to see its pixel dimensions and embedded resolution.
0%
File inspection
Image facts
Pixel dimensions—
Format—
Embedded resolution—
File size—
Resolution sources in this file
Print reality check
Will it work at your print size?
Pixel dimensions—not a metadata label—determine usable print detail.
Choose an image, then check a print size.
Need the file tagged as 300 DPI?
This changes safe resolution metadata only. It never invents pixels or improves image quality.
Supported JPEG, safe static PNG, and safe WebP metadata structures are available now.Complex or ambiguous structures are safely refused.
Download rewritten imageHow it works
A metadata change, not a resample.
- Choose, drop, or paste a JPEG, PNG, or WebP image.
- Review its pixel dimensions and embedded resolution.
- Choose Set metadata to 300 DPI when the file is in the safe rewrite subset.
- Download the result and re-check the downloaded file if your print workflow requires it.
300 DPI does not create detail. Print dimensions and usable detail still depend on the image's existing pixel dimensions. A metadata label cannot turn a small image into a higher-quality source.
Supported and refused cases
Gate B status: PASS_SAFE_SUBSET. The boundary below is deliberate: safe rewrites are narrower than format detection, and a refusal is a safe result.
Static PNG without eXIf or APNG animation metadata, including supported pHYs, ICC, color, and interlaced cases.
Supported VP8, VP8L, and VP8X structures can receive verified Exif resolution metadata while pixel payloads remain unchanged.
Complex, malformed, ambiguous, or unsupported structures receive a stable refusal. The converter does not claim that every image can be safely changed.
Privacy and download verification
Processing happens locally in your browser. The tool does not upload image bytes, filenames, or Exif metadata. Before download, it compares the rewritten bytes with the Blob bytes and checks the writer's invariants. Resetting or replacing an image revokes the current object URL.
Frequently asked questions
Does converting an image to 300 DPI add pixels?
No. This tool changes supported resolution metadata only. Pixel dimensions, image content, and encoded image data remain unchanged.
Which image formats can be rewritten?
The safe rewrite subset includes supported JPEG metadata layouts, static PNG files without eXIf or APNG animation metadata, and supported WebP structures. Unsupported or ambiguous structures are refused.
Are my images uploaded?
No. The image is read and processed locally in your browser. The page does not send the image, filename, or Exif metadata to a server.
Use the Image DPI Checker to inspect a file without rewriting it, or browse the image resolution guides for print and metadata explanations.