Compare JPG Images
Compare two JPG photos online and see the real differences. Adjustable tolerance filters out JPEG compression noise so only genuine changes light up. No upload.
Files never leave your browser.
Drop two JPGs to compare pixel by pixel. JPEG re-encoding leaves compression noise, so the tolerance slider defaults high enough to skip it; drop it to 0 if you need an exact compare.
About JPG Diff
Compares two JPEG photos pixel by pixel in your browser. JPEG is lossy, so every save changes pixels that look the same. The tolerance control hides that noise and leaves the real changes.
How to use
- Drop or pick the left photo. This page accepts .jpg and .jpeg files.
- Drop or pick the right photo. The tool measures how far the two frames differ and sets a start tolerance by itself.
- Raise Color tolerance while compression noise still shows, then raise Min group size to drop the last scattered pixels. Set the tolerance to 0 when both photos come from the same encoder and you want every changed pixel.
What this tool doesn't handle
- Two saves of one photo at different quality settings differ over the whole frame. Tolerance hides most of that, but a heavily compressed photo can still report broad noise.
- Only the decoded pixels are compared. EXIF fields, the embedded thumbnail and the colour profile are not read.
Frequently asked questions
Do my files ever leave my browser?
No. Every comparison runs locally in your browser. Nothing you paste, drop, or load is uploaded to a server; the tool keeps working even if you go offline after the page loads.
Is this tool free to use?
Yes. All DiffResolver tools are free, with no account, sign-up, or installation. Because processing happens on your device, there are no server-imposed usage limits.
Why do two JPG photos differ when the picture looks the same?
JPEG drops information on every save. A new save shifts colour values over the whole frame, mostly near edges. An exact compare therefore marks almost every pixel, which is why the tool starts with a tolerance that skips this noise.
Which tolerance fits a JPG compare?
Start with the value the page derives from your two photos. Lower it toward 0 when both files come from the same encoder at the same quality. Raise it when one photo is saved at a low quality.
Can I compare a JPG with a PNG?
Yes, but use Image Diff, which takes every picture format. This page limits the file picker to JPEG so both sides stay in one format.
Is there a file size limit?
No server limit applies, because nothing is uploaded. The memory of your device sets the practical limit. Above 10 MB for text, 40 MB for images, 100 MB for documents, or 500 MB for archives, the tool warns you that the work can be slow, but it never blocks the file.
Does this tool work offline?
Yes. The browser keeps a copy of the tool after the first visit, so a page you opened before still works without a network. You can also install DiffResolver as an app from the browser menu. Installation stays optional; the site works the same in a normal tab.
Where is my data stored?
Your files are stored nowhere. They stay in the memory of the page and are gone when you close the tab. Only what you save yourself stays in this browser: a snapshot, your tool options, and your theme. To remove it, open Settings and select Clear all local data.