Posterize Images Online
Reduce images to bold flat tones for poster art and screen prints. 2–16 levels per channel, instant results.
About the Posterize Image
Posterize quantizes each RGB channel to N discrete levels, collapsing smooth gradients into bold flat bands — the foundation of silkscreen and pop-art looks. Four levels channels Warhol; 8–10 gives a gentler illustrated feel.
How it works
The tool quantizes each RGB channel to a fixed number of levels: smooth gradients become visible steps, and photographs flatten into graphic, screen-print style art. Fewer levels means bolder simplification — at 3–4 levels a photo starts reading like an actual poster.
How to use it
Add up to 10 images, choose the level count (start at 6 and adjust), and process. Preview how gradients stepped, then download individually or as one ZIP.
Supported formats & limitations
Accepts .jpg, .png and .webp up to 30MB each, 10 per run. The flattening makes subsequent color work (duotone, palette extraction) cleaner, and PNG output avoids JPEG artifacts smearing the hard tonal edges posterization creates.
Common use cases
Designing gig posters and album art, creating stencil references for screen printing and spray paint, simplifying photos into painting references, and making bold, low-color graphics that compress beautifully.
Frequently asked questions
How private is Posterize Image?
Everything runs locally in your browser via the Canvas API. Your picture never leaves your machine — there is no upload step at all, so processing is as private as working in an offline editor.
What kind of image files work with this tool?
JPG, PNG or WEBP inputs are supported, up to 30 MB per file. For exotic formats, convert them first with one of the converter tools, then come back.
What are the size and batch limits?
You can queue 10 files per run, each up to 30 MB. Results download individually or bundled as a single ZIP.
Can I fine-tune the result before downloading?
You can adjust Tonal levels. Results are previewed after processing, so tweak values and re-run until the output looks right.
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