Merge JPG Images
Merge two JPG photos online by painting which parts to keep. Transparent areas flatten to white so the downloaded JPEG stays clean. Nothing is uploaded.
Files never leave your browser.
Compose two JPG photos by painting a per-pixel mask. The downloaded JPEG flattens transparent pixels over white so the result stays clean.
About JPG Merge
Builds one photo from two JPEG sources. You paint a mask that says which side each region comes from, and the detected differences seed it. The result downloads as a JPEG.
How to use
- Pick a left and a right photo of the same size.
- Paint the mask, or resolve each difference group with the buttons next to it.
- Set Download format to JPG and download the photo. Pick PNG instead when the result must stay exact.
What this tool doesn't handle
- A JPEG download is encoded again, so the result is not pixel-identical to either source.
- JPEG has no alpha channel. Pixels that stay transparent are flattened over white in the download.
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.
Does a JPG merge add compression artifacts?
The download is encoded once more as JPEG, which adds a light generation loss over the whole photo. Set Download format to PNG to keep the merged pixels exactly as you painted them.
What happens to transparent pixels?
JPEG cannot store transparency, so they are flattened over white. Merge to PNG or WebP when a source has an alpha channel.
Must both photos have the same size?
The mask needs one common size. Turn on Auto-scale and align mismatched sizes to fit the smaller photo onto the larger one, then correct scale and offset in the alignment workspace.
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.