Are my photos uploaded anywhere?

No. Every exposure is decoded, blended, and merged locally in your browser — nothing is sent to a server.

Does the order I add the photos matter?

No. The merge weighs each pixel by how well-exposed, contrasted, and saturated it is in each photo, not by the order the files were added — add them in any order.

Does this work with black-and-white photos?

Yes. Brightness and local contrast still drive which exposure wins at each pixel for grayscale images — a lack of color saturation doesn't exclude a photo from the blend.

Why do all my photos need to be the same resolution?

The merge blends pixel-by-pixel across exposures, and the result keeps the exact resolution you shot. Mismatched sizes can't be aligned automatically, so photos with a different resolution than the first one you add are skipped.

What does the Strength slider do?

It scales how much that exposure is allowed to contribute to the final blend. Turn one down if it's introducing noise or an unwanted color cast, or up if you want it to dominate the result.

HDR PHOTO MERGE

Blend bracketed exposures of the same scene into one HDR photo — full resolution, color or black-and-white. Nothing leaves your browser.

+ Add 2–5 exposures of the same scene

Same framing, same resolution — nothing uploaded, everything stays in your browser.

How to merge exposures into one HDR photo

1
Add 2 to 5 photos of the same scene shot at different exposures — same framing, same resolution, ideally from a tripod.
2
Drag each exposure's Strength slider if one should pull the blend toward it more or less.
3
Set the overall Brightness and Contrast for the merged result.
4
Click Merge to HDR, preview the result, and download it.

Questions

Are my photos uploaded anywhere?: No. Every exposure is decoded, blended, and merged locally in your browser — nothing is sent to a server.
Does the order I add the photos matter?: No. The merge weighs each pixel by how well-exposed, contrasted, and saturated it is in each photo, not by the order the files were added — add them in any order.
Does this work with black-and-white photos?: Yes. Brightness and local contrast still drive which exposure wins at each pixel for grayscale images — a lack of color saturation doesn't exclude a photo from the blend.
Why do all my photos need to be the same resolution?: The merge blends pixel-by-pixel across exposures, and the result keeps the exact resolution you shot. Mismatched sizes can't be aligned automatically, so photos with a different resolution than the first one you add are skipped.
What does the Strength slider do?: It scales how much that exposure is allowed to contribute to the final blend. Turn one down if it's introducing noise or an unwanted color cast, or up if you want it to dominate the result.