Fix a dull or dim photo with two sliders in one pass: contrast to separate the tones, then brightness to place them. Live preview, batch, and no upload.
Applies contrast and brightness together in the order editors use: the contrast curve first, stretching tones around mid-grey, then a brightness offset that adds or subtracts the same amount from every channel. Doing both in one pass means the two sliders behave predictably together and there is only one rounding step, so the result is a little cleaner than running the two single-purpose tools back to back. Both sliders sit at zero for no change and run from −100 to +100.
A phone photo of a whiteboard: the board reads as pixel value 180 instead of white and the marker as 90 instead of black. Contrast +40 pushes the board to about 200 and the marker to 62. Brightness +30 then lifts everything, so the board reaches 230 and the marker sits at 92, which prints as clean white paper with dark, legible writing. The same +40 / +30 on a dusk street scene would blow the streetlights out, so for photos with real highlights keep brightness under +15.
This is the tool for scans, whiteboards, receipts, screenshots and flat overcast photos, where you need both sliders and want to see them interact. If only one thing is wrong, the single-purpose tools have finer ranges: Change Brightness multiplies instead of adding, which suits underexposed photos better, and Change Contrast goes up to 200 percent. For lifting shadows without brightening highlights, Adjust Gamma is the right curve. Avoid large positive brightness on anything with sky or white clothing.
Brightness adds a fixed amount to every pixel, so +30 moves a value of 100 to 130 and a value of 220 to 250; anything past 255 clips to white. Contrast follows the standard 259-formula curve used in most editors, so +25 here looks like +25 elsewhere. The chips set common values and Reset both returns to zero. Output format and JPEG quality live in the Output section; Same keeps the original type.
Why is the result different from doing brightness then contrast separately? Order matters. This tool applies contrast first and brightness second, which keeps the brightness shift from being amplified. If you run Change Brightness and then Change Contrast, the contrast curve also stretches the shift you just added.
The picture went grey when I lowered contrast. Is that a bug? No. Negative contrast pulls every tone towards mid-grey, and at −100 the whole image is one flat grey. Use small negative values, around −10 to −25, to soften a harsh image.
Can I apply the same fix to a whole folder of scans? Yes. Switch on Batch mode or drop several files; the same two values are applied to each and you download one ZIP.
Are my images uploaded? No. The adjustment runs in your browser on your device. Nothing is sent anywhere.