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Open the Img Stop Check Image DPI tool and drop one or more images. It reads the DPI stored in the file (JFIF, EXIF, Photoshop or PNG pHYs), shows the pixel size, the print size at that DPI and at 72, 96, 150, 300 and your own DPI, and rates how sharp A6 to A3, 4×6, 5×7 and 8×10 prints will be. Use Change DPI to set a new value.
About the Check Image DPI
The Img Stop Check Image DPI tool tells you two things at once: the DPI value written inside the file, and – more importantly – how large the picture can really be printed. DPI is only a label; the pixels decide print quality. That is why the tool shows the print size at the stored DPI as well as at the common 150 and 300 DPI.
Drop JPG, PNG, WebP, TIFF or BMP files (HEIC and AVIF are read where possible) and get a card for each with the pixel size, megapixels, DPI and its source, print sizes in centimetres, millimetres or inches, and a table showing the effective DPI and quality for standard paper and photo sizes. Several files also get a comparison table.
Key features
- Reads stored DPIJFIF, EXIF, Photoshop resolution and PNG pHYs, plus TIFF and BMP headers.
- Print size calculatorAt the file’s DPI and at 72, 96, 150, 300 and a custom DPI.
- Paper size checkEffective DPI and quality for A6, A5, A4, A3, 4×6, 5×7 and 8×10.
- cm, mm or inchesSwitch units at any time.
- Many files at onceA summary table compares every image.
- Change DPI linkJump to the Change DPI tool to write a new value.
How to use the Check Image DPI
- Add images Drop one or more image files.
- Read the DPI See the stored DPI, where it came from and the pixel size.
- Check print sizes Compare sizes at different DPI values and the paper size table.
- Change if needed Use Change DPI to set 300 DPI or another value without losing quality.
Check Image DPI at a glance
| Price | Free |
|---|---|
| Formats | JPG, PNG, WebP, TIFF, BMP (HEIC/AVIF where possible) |
| Sources | JFIF, EXIF, Photoshop, PNG pHYs |
| Units | cm, mm, inches |
| Paper sizes | A6–A3, 4×6, 5×7, 8×10 |
| Processing | In your browser – files are not uploaded |
When to use it
- Check that photos meet a print shop’s 300 DPI requirement.
- Find out how big a phone photo can be printed sharply.
- Verify image DPI for passport, visa and exam forms.
- Check artwork before sending it to a printer or publisher.
- Compare the resolution of several images at once.
Tips for the best result
- If DPI is “Not set”, most apps assume 72 or 96 DPI – the pixels are what really matter.
- For photo prints, aim for 300 effective DPI; 150 DPI is fine for posters seen from a distance.
- Changing the DPI value alone does not add detail – it only changes the default print size.
- Social networks remove DPI information, so downloaded images often show no DPI.
- To enlarge a small image for printing, try Upscale Image first.
Frequently asked questions
How do I check the DPI of an image?
Drop the image into the Img Stop Check Image DPI tool. It shows the DPI stored in the file and where it was found, along with the pixel size and print size.
What does “DPI not set” mean?
The file has no resolution value, so programs fall back to a default – usually 72 DPI on Mac and in Photoshop, or 96 DPI in Windows. The image itself is unaffected.
How big can I print my photo?
Divide the pixels by 300 for top quality: a 3000 × 2000 px photo prints sharply at 10 × 6.7 inches (25.4 × 16.9 cm). The tool calculates this and rates common paper sizes for you.
Why do two DPI values disagree?
A file can store DPI in several places (for example JFIF and EXIF). The tool shows the value most programs use and tells you when others differ.
Does a higher DPI make an image better?
No. DPI is only a print setting; detail comes from the number of pixels. Raising the DPI makes the default print smaller, not sharper.
How do I change the DPI?
Click Change DPI to open the Change DPI tool, choose 300 or another value and save – the pixels are not changed.
Learn more
- MDN: Image file types – common image formats explained
Made and maintained by the Img Stop team.