Custom Duotone image converter
Create two-color dithered images with any shadow and highlight color you choose. Free online duotone dithering tool for brand-matched art.
About the Custom Duotone palette
A duotone maps every shade of an image onto a ramp between two colors of your choice. With dithering, those two flat colors still convey full tonal detail.
Pick a shadow and highlight that match your brand, then export crisp graphics for social media, posters, website heroes or risograph printing.
Colors
Best for
- Brand-colored graphics
- Risograph prints
- Website hero images
How to dither an image
- Add your image. Click Upload image, drag a file onto the preview, or paste with Ctrl/⌘+V. JPG, PNG, WebP and GIF work.
- Pick an algorithm and palette. Error diffusion (Floyd–Steinberg, Atkinson…) for photos, Bayer for a retro crosshatch.
- Tune it. Raise pixel size for chunkier pixels; adjust brightness and contrast to control which tones become dark or light.
- Download. Export a lossless PNG at up to 8× with crisp nearest-neighbour scaling.
FAQ
What is Custom Duotone palette dithering?
A duotone maps every shade of an image onto a ramp between two colors of your choice. With dithering, those two flat colors still convey full tonal detail.
When should I use Custom Duotone?
Custom Duotone works best for: brand-colored graphics, risograph prints, website hero images.
Is DitherImage free?
Yes. DitherImage is completely free with no sign-up, no watermark and no usage limits.
Are my images uploaded to a server?
No. All processing happens locally in your browser using JavaScript and the Canvas API. Your images never leave your device.