Upload an image to apply a duotone effect
Accepted formats: JPG, PNG, WEBP, BMP, GIF (non-animated)
Paste (Ctrl/⌘+V) or drop an image — or import from a URL
A duotone takes a single image and remaps its full range of tones to a gradient between just two colors — one for the shadows and one for the highlights. It is the bold, graphic look you see on concert posters, magazine spreads, and album covers. Image Machine's duotone generator reads each pixel's brightness and maps it onto your chosen shadow and highlight colors, so darker areas pick up one hue and brighter areas the other, with a smooth gradient in between. Pick from ready-made color pairs or set your own with the color pickers, blend the effect back toward the original with the intensity slider, and download a PNG. Everything runs locally in your browser, so your image is never uploaded.
How It Works
Choose a tool
Pick from 120+ tools to resize, convert, compress, or enhance your image.
Upload & edit
Drag and drop your image and adjust the settings. It stays on your device.
Download
Save your result instantly — no watermark, no sign-up required.
Why Image Machine?
Your files never leave your device
All processing runs locally in your browser. Your images are never uploaded to a server.
Completely free
Every tool is free, with no limits, no watermarks, and no hidden costs.
Lightning fast
No upload waiting — your images are processed instantly on your own device.
Professional quality
Pixel-perfect output with full control over format, size, and quality.
Frequently Asked Questions
What is a duotone effect?
A duotone replaces every tone in an image with a blend of two colors — one mapped to the dark areas and one to the light areas. Instead of a full-color photo or a plain black-and-white one, you get a striking two-color image where brightness, not the original hue, decides the color. It is a staple of poster, editorial, and album-cover design.
How do I choose good duotone colors?
A classic combination uses a dark, saturated color for the shadows and a bright, warm color for the highlights — for example deep indigo with gold, or navy with coral. High contrast between the two colors gives a bold graphic look, while closer colors give a subtle tint. Try the presets first, then fine-tune with the color pickers.
Is my image uploaded anywhere?
No. The duotone effect is applied entirely in your browser using your device's own processor. Your photo never leaves your computer, nothing is sent to a server, and transparent PNG areas stay transparent.