Curves
The precise way to shape contrast and colour — with a live histogram.
Drop an image here
precise tonal control — processed on this device
You can also paste from the clipboard.
Frequently asked questions
How do I use a curve?
The diagonal line maps input brightness (left to right) to output brightness (bottom to top). Drag a point above the line to brighten that range, below to darken. A gentle S — shadows down, highlights up — is the classic contrast boost.
What is the grey shape behind the grid?
A histogram: how many pixels sit at each brightness. A pile against the left edge means crushed shadows, against the right means blown highlights. It shows the original image, so you can see what you're working with.
How do I fix a colour cast?
Switch to the channel that's too strong and pull its curve down slightly in the midtones — or lift the opposite channel. For a photo that's too blue, ease the Blue curve down around the middle.
Why don't the highlights blow out when I pull hard?
The curve is interpolated with a monotone spline, which never overshoots between your points. Ordinary splines can bulge past the values you set and clip tones you didn't touch.
Are my images uploaded to a server?
No. SqueezePix runs entirely in your browser — files are opened and processed on your own device and never transmitted anywhere. You can even load the page, go offline, and keep working.