About this tool
Adjust an image's brightness, contrast, and saturation right in your browser, for free, or apply a grayscale, sepia, or invert filter. Drag a slider to preview a change live, and it applies as soon as you release it; a filter applies the moment you click it. Undo, redo, or reset the image at any point. Nothing ever leaves your device.
Each slider runs from -100 to +100, with 0 as the untouched original -- no separate "Apply" button, since releasing a slider (or pressing an arrow key while it's focused) commits that adjustment on its own. Filters work the same way: clicking Grayscale, Sepia, or Invert commits immediately as its own step, and you can still layer brightness, contrast, or saturation changes on top afterward. "Auto adjust" builds a brightness histogram from the image, clips the darkest and lightest outliers, and works out brightness/contrast values that stretch the image toward using more of its available tonal range -- the same basic idea behind an auto-levels feature in a full photo editor.
Frequently asked questions
What does the "Auto adjust" button do?
It builds a brightness histogram from the image, clips the darkest and lightest 0.5% of pixels as outliers, and calculates brightness and contrast values that stretch the image toward using more of its available tonal range. It's a quick starting point -- you can still fine-tune the sliders afterward.
What does a value of 0 mean on the sliders?
0 is the untouched original -- no brightness, contrast, or saturation change applied. Positive values increase that property; negative values decrease it, down to -100 for fully desaturated (in the saturation slider's case) or a much darker/flatter image (for brightness/contrast).
Do I need to click an "Apply" button to save a slider change?
No -- releasing a slider (or finishing a keyboard nudge while it's focused) commits that adjustment automatically. Undo and redo step back and forth through each committed change, and "Reset image" jumps straight back to the original.
Can I undo an adjustment after applying it?
Yes -- every committed slider change is its own undo-able step. Use the undo/redo buttons to move through your edit history, or reset the image entirely to start over from the original file.
Can I combine a filter with the brightness, contrast, or saturation sliders?
Yes -- clicking Grayscale, Sepia, or Invert applies immediately as its own step, and any slider changes you make afterward layer on top of it. Each one is its own separate entry in your undo history.