Duotone Effect
Map image brightness to a two-color gradient (shadow → highlight).
How to Use
- Drop image.
- Pick shadow + highlight colors.
- Adjust contrast.
Notes
About the Duotone Effect
The Duotone Effect is a free tool for image, audio and file tasks. It runs right in your web browser, so there is nothing to download. Map image brightness to a two-color gradient (shadow → highlight).
How it works
Enter what you have and read the result as it updates live. It all runs on your own device, so it is quick and private, with nothing to install.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
How it works?
Each pixel's luminance picks a color between the two selected.
How do I use the Duotone Effect?
Simply type your numbers and read the result, which refreshes the instant you change something. There is nothing to submit and nothing to wait for.
Is it free? Does it work without internet?
Yes to both. It is free with no sign-up, and once the page has loaded it keeps working even with no internet.
Where does my data go?
Nowhere — every calculation runs on your own device. Nothing you enter is uploaded, logged, or stored.
Common Use Cases
Brand imagery
Consistent color palette.
Poster
Bold two-tone look.
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