Our free online duotone effect generator creates stunning Spotify-style two-color images perfect for album covers, posters, social media, and creative designs. Duotone is a classic photographic technique that maps the brightness values of an image to two colors - a shadow color for dark areas and a highlight color for bright areas. This creates a bold, artistic look popularized by Spotify's branded imagery. Choose from 12 carefully crafted presets or create custom color combinations with our intuitive color pickers.

Duotone works by first converting your image to grayscale, then mapping brightness values to a gradient between two colors. The shadow color replaces pure black and dark tones, while the highlight color replaces pure white and bright tones. Mid-tones get a blend of both colors proportional to their brightness.

For best results, choose colors with good contrast. Complementary colors (opposite on the color wheel) create vibrant, eye-catching effects. Analogous colors (adjacent on the wheel) produce harmonious, subtle results. Classic combinations like blue and orange (Spotify's signature) work well because they provide strong visual contrast while remaining aesthetically pleasing.

Consider your image content when selecting colors. Portraits often work well with warmer shadow colors (browns, burgundy) and cooler highlights (cream, light blue). Landscapes can handle bolder combinations. Highly detailed images show more color gradation, while high-contrast images produce more dramatic duotone effects with distinct color zones.