Levels
Black point, white point, midtones.
This runs in your browser. Nothing is uploaded.
About Levels
Sets a black point, a white point and a midtone gamma to stretch a flat image back across the full tonal range, with all three controls applied in your browser.
Scans are the classic case. A document photographed on a phone comes back with paper that's grey rather than white and text that's charcoal rather than black, and no amount of brightness fixes both ends at once. Levels does, because it lets you state where black should begin, where white should begin, and how the middle sits between the two.
Black and White both run on a 0 to 255 scale. Anything at or below your black point becomes 0, anything at or above your white point becomes 255, and everything between is rescaled to fill the gap. Gamma, from 0.2 to 3, then bends the middle: above 1 lifts the midtones without moving either endpoint, below 1 presses them down.
The rescaling is destructive on purpose. Tones cut off at either end are genuinely discarded, so a black point of 60 on a photograph means every shadow detail below 60 merges into one flat black. On a document that's precisely what you want. On a portrait it isn't. Run the histogram tool first and you'll see where the real data starts and stops instead of guessing.
How to use Levels
- 1Load an image by dropping it on the panel or browsing for it.
- 2Set Black and White to bracket the tones worth keeping, both on a 0 to 255 scale.
- 3Adjust Gamma — above 1 brightens midtones, below 1 darkens them.
- 4Click Apply preview, then Download to save the result.
What it won't do
- One mapping shared by all three channels; no separate red, green or blue controls.
- Tones outside the black and white points are discarded rather than compressed.
- Setting the white point below the black point gives a near-binary image, not an inversion.
Common questions
What's the difference between levels and brightness/contrast?
Levels gives you independent control of the two ends of the tonal range plus the middle; brightness and contrast give you one shift and one stretch around a fixed centre. When a scan has grey paper and washed-out text, levels corrects both ends separately. Brightness and contrast will always trade one against the other.
What does the gamma slider actually do?
Gamma brightens or darkens the midtones while leaving pure black and pure white exactly where they are. Values above 1 lift the middle, which is the usual move for a photo that's dark overall but has correct highlights. Values below 1 deepen it. The range runs 0.2 to 3, and the neutral setting is 1.
Will levels fix a colour cast?
No. The same mapping is applied to red, green and blue, so the relationship between the channels — which is what a cast is — survives untouched. Correcting a cast needs per-channel control, which this page doesn't offer. For an ordinary warm or cool cast, the white balance tool moves red against blue instead.
How do I know where to put the black and white points?
Run the histogram tool on the same file first. It plots how many pixels sit at each value, and the sensible place for your points is where the data actually begins and ends. If the graph starts at 40 and stops at 210, entering those two numbers uses the full range without throwing anything away.
Related tools
Why this one doesn't upload your file
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