The short answer
Why use Size Finder?
Upload forms reject photos for being too big, too small or the wrong shape, and rarely say which. Checking the real numbers first shows what you need to change before you try again.
After you tap Apply changes, the panel lists file size, dimensions in pixels, aspect ratio, megapixels, print size at 300 DPI, and MIME type. The MIME type is the one your browser assigns from the file extension, so it will not catch a PNG that was renamed to .jpg. Download result saves the list as a .txt file.
Dimensions follow the photo's orientation tag, so a portrait phone shot reads taller than wide even though the sensor stored it sideways. File size is the size on disk, which depends on compression: two photos of the same pixel size can differ tenfold in KB. To make the file smaller without changing the pixels, use Compress Image.
Aspect Ratio and Megapixel produce the same report but their pages explain those figures in depth. Image Viewer shows the photo full size with the key numbers in the status line. For the DPI value stored in the file, which some print forms ask for, use DPI Checker.
Where Size Finder fits
Exam forms
Check a passport photo against an exam portal's pixel and KB limits before uploading.
Email attachments
See how heavy a photo is before attaching several to one message.
Website images
Spot oversized images before adding them to a blog post or shop listing.
Start to finish
How to use Size Finder
- 01Tap Choose image and pick the photo a form or website keeps rejecting.
- 02Tap Apply changes and compare the pixel dimensions and file size with the form's stated limits.
- 03Tap Download result if you want the report kept as a .txt file, named after the image.
What to expect from Size Finder
| Check | What it means here |
|---|---|
| Supported input | JPEG, PNG, WebP, GIF, BMP, SVG and browser-supported AVIF images |
| Main controls | Choose a file; the results are read-only |
| Output | Dimensions, metadata, colors, or an extracted preview, depending on the tool |
| Working limit | 50 MB and 50 megapixels per image |
Size Finder tips
- Here 1 KB is 1,024 bytes; leave a little room under a strict KB limit.
- The MIME type comes from the extension, so it will not expose a renamed file.
- Two photos with the same pixels can differ tenfold in file size.
- HEIC opens only in browsers that decode it, such as Safari.
Size Finder FAQ
Something missing? Ask us.
Is the file size in KB the same as my computer shows?
My form says the photo must be 600 × 600. How do I fix it?
Are there limits on what it can read?
Does Size Finder upload my file?
Is Size Finder free to use?
Why did Size Finder fail or look wrong?
Related tools
More in Image Information.