What you need
Choose one still JPEG, PNG, or WebP file up to 20 MB. Use a clean, high-quality source you are authorised to edit.
Image Tools / Local studio
Map image luminance between custom shadow and highlight colours to create a controlled two-colour PNG.
Step 1 / Source
Or browse for a JPEG, PNG, or WebP image that you own or are authorised to edit.
One file · up to 20 MB · maximum 50 megapixelsStep 2 / Output
Configure two mapped colours. Processing remains inside this browser tab.
The selected image is decoded and re-encoded inside this browser tab.
After download, the preview URL, decoded bitmap, canvas, and selected source reference are cleared.
Nirmion cannot remove the finished file from your device or browser download history.
Workflow guide
Choose one still JPEG, PNG, or WebP file up to 20 MB. Use a clean, high-quality source you are authorised to edit.
Original hues are intentionally replaced. Check faces, text, logos, overlays, and the destination platform before publishing.
Receive a duotone PNG. The selected source and temporary decoding memory are released after processing.
Decision guide
Duotone Maker is designed around two mapped colours. The right setting depends on the destination, viewing size, source quality, and whether later editing is expected.
Original hues are intentionally replaced. Browser processing avoids a Nirmion upload, but it does not change copies already stored on your device, in backups, or on publishing platforms.
Good to know