Photo Duotone

Photo Duotone reimagines any picture in just two colours — one for the shadows and one for the highlights — for the bold, editorial look made famous by Spotify covers, poster art and brand campaigns.

Drop in a JPEG, PNG, WebP or GIF and it is decoded, mapped and previewed entirely inside your browser.

The process starts by reading each pixel's perceptual brightness using the standard luminance weights, which keeps the tonal structure of the original intact.

That brightness, from black to white, is then used to interpolate between your two chosen colours: the darkest tones take your shadow colour, the brightest take your highlight colour, and everything in between rides a smooth gradient across the two.

Because it works from real luminance rather than a flat overlay, faces, edges and depth all stay readable while the palette is completely transformed.

Pick both colours with the native swatches and the preview re-renders from the original pixels instantly, so you can explore combinations — navy-and-gold, teal-and-pink, classic black-and-cream — without the effect ever compounding.

Everything runs locally with the Canvas API, so your image is never uploaded, stored or logged, and the tool works offline once loaded.

When the palette sings, download a lossless PNG.