Grayscale & Filter Converter
Convert any image to grayscale (true luminance-based), sepia tone, or inverted colors. Side-by-side preview lets you compare before and after. Output is always lossless PNG so there's no quality loss from the conversion.
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Convert to grayscale, sepia tone, or inverted — lossless PNG output, browser-only
How it works
- Drop any colour image — PNG, JPG, WebP, or AVIF
- Select the effect: Grayscale (luminance-weighted), Sepia (warm brown tone), or Invert (negative)
- Download the result as a lossless PNG — all colours are converted, transparency is preserved
Frequently asked questions
What is luminance-weighted grayscale?
Human eyes are more sensitive to green than red or blue. Luminance weighting (0.299R + 0.587G + 0.114B) produces a natural-looking black and white rather than a flat average of the three channels.
Does the grayscale conversion work on transparent PNGs?
Yes. The tool converts only the RGB channels — the alpha channel is preserved unchanged. A transparent PNG remains transparent after conversion.
What is the difference between Sepia and a warm photo filter?
Sepia applies a fixed warm-tinted desaturation that mimics aged photographic prints. The Image Filter tool offers more nuanced LUT-based film grade presets for modern colour work.
Related tools
Why it's different
Grayscale, sepia, and invert applied via luminance-correct algorithms — no upload, no server, your images stay private.
100% Private
Everything runs on your device using in-browser AI. Nothing is transmitted to any server — not the file, not metadata, not filenames.
True Alpha Channel
We export straight (non-premultiplied) alpha so transparent PNGs open with a real checkerboard in Photoshop and Figma — no black halos.
Free Forever
No paywall, no watermark, no premium tier. The full-quality AI is free, supported by non-intrusive ads.
Works Offline
Once loaded, the app and AI models cache locally. Process files without an internet connection. Installable as a desktop or mobile app.
Ready to try it?
Free, private, no signup. Lossless PNG output.
Convert to grayscale →