Pixel Art Palette Extractor — .gpl, HEX and JSON
Get the real palette of a sprite — every colour with its pixel count and share — from one image or a whole animation, then keep it under a colour budget.
- PNG framesMeasured· Pillow
- PaletteMeasured· re-import
- pixel-lab.jsonUNVERIFIED
What it does
- Palette from all frames at once, with exact per-colour counts and percentages.
- Sort by lightness, hue, saturation or frequency (greys grouped at the end of a hue sort).
- Colour budget audit: target vs actual, the rarest colours listed, one-click merge into their nearest survivor.
- Import and export GIMP .gpl, Lospec-style HEX lists and JSON; the format is read from the content, not the extension.
How to do it
- Drop the image or frames.
- Set the number of colours and sort order.
- Optional: set a colour budget and merge the rarest colours.
- Export the palette (.gpl, .hex or .json) or the recoloured frames.
Outputs and how each was checked
"Measured" means the downloaded file was opened again outside the page (Pillow, numpy or an independent parser) and the property was measured. Loading these files in a game engine was not tested.
| Target | Files | Check |
|---|---|---|
| PNG frames | anim_N.png · 1×–8× nearest | Measured PillowEvery exported colour re-read from the PNGs lies inside the locked palette. |
| Palette | .gpl · .hex (Lospec) · .json | Measured re-importEach format was exported and imported back through the UI: 16 → 16 colours. |
| pixel-lab.json | generic frames + palette | UNVERIFIEDGeneric JSON; not loaded in any engine. |
Evidence
8 anti-aliased frames → one 16-colour palette with 0 exported colours outside it; an unchanged region identical in all 8 frames with dithering off and with Bayer 4×4; the anti-alias remover took 271 colours to 16 without moving a single silhouette pixel; integer scale, offset and 2.5× non-integer scaling detected exactly.
Limits
- Frames larger than 4096 × 4096 are refused: every pass runs on the main thread, and there is no cancel button yet.
- A sprite sheet is treated as one image; cut it into frames first (sprite sheet cutter).
- With a dithering mode on, the cleanup counts include dither pixels; set dithering to None first.
- The exported JSON is generic; importing it into Godot or Unity was not tested.
Questions
Are the pixel counts exact?
Yes, for animations up to 4 megapixels of total frame area; above that the counts cover the visible frame and the panel says so.
Can it read a .txt that holds a GIMP palette?
Yes. The format is detected from the content, so a .txt with a GIMP header is read as .gpl.
Is it free, and do I need an account?
Everything on these pages is free and works without an account. There is no watermark and no export that is held back.
Are my sprites uploaded?
No. The Studio decodes, packs and exports in this browser tab. Projects are autosaved in the browser (IndexedDB) and can be saved as a .nerulio file.
Does it need Aseprite or an engine plugin installed?
No. .aseprite files are read and written in the browser, and each engine bundle carries what that engine needs (for Godot, the import settings and scene; for Unity and the Godot TileSet, a small editor script).