DPI marker notes
The tool updates the DPI/PPI marker in JPG or PNG files so print-oriented software can read a different physical-size hint.
It does not invent pixels, sharpen the photo or make a low-resolution image suitable for every print size.
Change Image DPI
Update the DPI/PPI marker in a JPG or PNG file for print and document workflows while keeping clear that DPI does not add real image detail.
JPG and PNG DPI markerPrint-size estimateLocal downloadNo quality-upscaling claim
Image DPI changer
Result preview
Choose an image or enter dimensions to see results.
Choose an image or enter dimensions to see results.
How it works
- 1Choose a JPG or PNG image.
- 2Enter the target DPI requested by your printer, form or design workflow.
- 3Download a copy with the DPI marker updated, then check the estimated print size.
Privacy and limits
- Changing DPI does not increase pixel dimensions, sharpness or real detail.
- Some apps ignore DPI metadata and use pixel dimensions instead.
- Files are processed locally and are not uploaded.
Common use cases
- Set a JPG or PNG to 300 DPI for a print handoff
- Check how print size changes at 150, 300 or 600 DPI
- Prepare a document upload that expects a DPI marker
Format notes
- JPG density is written through the JFIF marker when possible.
- PNG density is written through the pHYs chunk.
- Some apps ignore DPI metadata and use only pixel dimensions.
Original test sample
- Set a 3000 x 2400 image to 300 DPI and confirm the estimated print size is 10 x 8 inches.
- Set the same file to 150 DPI and confirm the estimated print size doubles.
Frequently asked questions
Are my images uploaded?
No. ImgShrink processes selected images in your browser and does not upload them to a server.
Can this tool guarantee an exact file size?
No. Target compression gets close when possible, but the final bytes depend on image detail, dimensions, format and browser encoding.
Why is an output format unavailable or different?
The browser controls image decoding and export support. Some browsers may not export AVIF or may flatten unsupported transparency.
Source and compatibility notes
This tool works in the browser, so output support depends on what your browser can read and export.
Last checked: 2026-09-07
Notes
- No server-side image processing is used.
- Output format support depends on the browser.
- Animated images and metadata are not treated as guaranteed preserved data.
Related print size tools
All toolsCalculate how large an image can print from pixel dimensions and DPI. See inches, centimeters and print quality notes.
Convert image pixels to inches using DPI. Calculate width, height and print size directly in your browser.
Convert image pixels to centimeters using DPI. Get print dimensions in cm with inch and DPI context.
Resize images by width and height in your browser. Create smaller JPG, PNG or WebP files without uploading.