Duotone Photo Effect: Two-colour gradient-map photos with presets. Input: Image files. Output: Results shown on the page and a downloaded file. Privacy: Runs in your browser: inputs and files stay on your device and are not uploaded.
How to make a duotone image
- Drop a photo; Duotone is selected.
- Pick a preset pair or choose your own shadow and highlight colours.
- Adjust contrast to make the image punchier or softer, then download.
About duotone
A duotone uses just two colours: each pixel's brightness picks a colour on the gradient from the shadow colour to the highlight colour. The technique comes from printing, where two inks were used to add depth to monochrome photos, and became a modern design trend through Spotify's bold campaigns and countless posters and websites. Duotones work well for unifying photos of different styles in a series, placing text over images and matching brand colours.
Choose a dark shadow colour and a light highlight colour for clear images; similar brightness values flatten the picture. The conversion uses perceptual luminance (0.299 R + 0.587 G + 0.114 B) and runs locally in your browser, so your photos are never uploaded.
FAQ
Can I use my brand colours?
Yes. Set the shadow and highlight pickers to your colours.
What photos work best?
High-contrast images with clear subjects, like portraits or architecture.
Is it the same as a gradient map?
Yes, a two-colour gradient map.