Curves Adjustment

Adjust photo curves online for free: bend the RGB tone curve or a single color channel and watch brightness, contrast and color follow.

or browse filesdrop an image here or paste

Curves Adjustment result
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Adjust Image Curves Online

Curves is the tone control photographers reach for when a single brightness or contrast slider is too blunt. The graph maps every input tone, shadows on the left and highlights on the right, to an output tone: a straight diagonal line leaves the picture as it is, and bending the line changes exactly the tones under the bend. Lift the middle and the midtones brighten while black and white stay put; pull the lower quarter down and the upper quarter up and you get the classic S-curve that adds punch without clipping. This tool is that curves dialog in the browser, with the picture's histogram drawn faintly behind the graph so you can see where its shadows, midtones and highlights actually sit. The download is the original photo at full resolution with the curve applied.

How to Use the Curves Tool

  1. Open a photo. Click Select image, drop a file on the page, or paste it.
  2. Bend the line. Press anywhere on the line and drag: a point appears there and follows your finger or mouse. Drag up to lighten those tones, down to darken them. A tap without a drag only adds the point, so the picture does not jump.
  3. Add more points for finer control. Up to 16 points per curve. Pressing near an existing point picks it up instead of adding a new one. The input and output value of the point in hand show in the corner of the graph.
  4. Remove a point. Drag it off the graph and let go, or double-click (double-tap) it. The two end points stay, but you can drag them: raising the black end gives the faded, matte look, lowering the white end dims the highlights.
  5. Download. Save as PNG, JPG or WebP, or copy the result to the clipboard.

On a computer, the arrow keys nudge the selected point by one step (Shift for ten) and Delete removes it.

RGB and the Red, Green and Blue Curves

The RGB curve changes all three color channels together, so it moves brightness and contrast while the color balance stays as it was. Switch to Red, Green or Blue to bend one channel alone, which is how color casts are fixed and color grades are made: lift the red curve's midtones for warmth, or lower the blue in the shadows and raise it in the highlights for the teal-and-orange look. Each channel keeps its own curve, and the edited ones stay visible faintly on the graph while you work on another. The channel curve is applied first and the RGB curve on top of it, the same order photo editors use.

Presets

The menu under the graph shapes the channel you are on: More contrast and Strong contrast are gentle and steep S-curves, Brighten and Darken move the midtones, Faded matte lifts the blacks and dims the whites, and Negative inverts the tones. Every preset is an ordinary curve you can keep dragging, and Reset straightens all four curves at once. For a single-number fix, levels sets black and white points, gamma and exposure move the tones evenly, and contrast stretches around the middle.

Your Photo Stays on Your Device

A curves edit is usually the last step on a photo you care about, often straight from a camera or a phone. The whole adjustment runs in your browser on the original pixels: nothing is uploaded, there is no signup and no watermark, and transparent areas of a PNG stay transparent.

Frequently Asked Questions About Curves Adjustment

What is a curves adjustment?

A tone correction that remaps every brightness value of a picture through a curve you shape with points. Anything above the diagonal gets lighter and anything below gets darker, so one tone range can be changed without touching the others, which a plain brightness or contrast slider cannot do.

How do I make an S-curve for more contrast?

Add a point about a quarter of the way in and drag it down a little, then add one three quarters of the way in and drag it up the same amount. Shadows get darker and highlights lighter while the middle stays put. The More contrast preset draws a gentle one for you.

Why does the curve never swing past my points?

The line through the points is a smooth curve that stays between each pair of neighboring points instead of bulging past them. Two points placed close together therefore never make the curve dip below black or overshoot white somewhere you did not touch.

Can I fix a color cast with curves?

Yes. Pick the channel that is too strong or too weak, for example Blue for a picture that looks too cold, and pull the middle of that curve down or up until neutral greys look grey again.

Is my image uploaded to a server?

No. The photo is decoded, adjusted and saved inside your browser, so the original never leaves your device, and the download is made from the full-resolution original, not from the smaller preview on screen.