Auto-Trim Transparent Edges from PNG
Drop PNGs with transparent borders and the tool finds the tight bounding box around the actual artwork and crops to it — removing the empty space around logos, icons, stickers, signatures, and sprite frames. Adjust the alpha threshold to also strip near-transparent anti-aliased halos. Runs entirely in your browser, batch-ready, with no upload.
Drop PNG files here
Multiple files allowed
Picking the alpha threshold
A pixel is treated as empty when its alpha is at or below the threshold:
- 0 (default) — only fully transparent pixels are trimmed. Safe for almost everything.
- 10–20 — also drops near-transparent anti-aliased edge halos. Useful for icons with feathered edges.
- 50+ — aggressive. May eat into faint shadows or partially transparent content.
When to use auto-trim
- Icon export from Figma / Sketch. Trim the padding the export pipeline left around the icon.
- Sprite frames. Tighten each frame so the sprite sheet packs efficiently — combine with Sprite sheet.
- Signatures. First photograph it on white paper, run through Background remove to make the white transparent, then auto-trim → tight signature PNG.
- Stickers / die-cuts. Background-remove then auto-trim each.
- Scaled-up renders. Strip the empty border around an upscaled icon.
FAQ
Can it trim a solid white (non-transparent) border?
Not directly — auto-trim works on the alpha channel, so it removes transparent space, not coloured space. To trim a solid white margin, first make white transparent with Background (remove mode), then auto-trim. For a known fixed margin, Crop by coordinates is faster.
What if my image is fully opaque?
Nothing is trimmed — output is the same dimensions as the input.
What if my image is fully transparent?
The tool reports "all transparent — nothing to trim" and skips that file.
Will it crop into the actual content?
No (at threshold 0). Only fully-transparent edge pixels are dropped — interior content is untouched. At higher thresholds you can lose feathered edges; bump down to 0 if you see clipping.
What about JPG inputs?
JPG has no transparency, so there's nothing to trim — auto-trim is a PNG-only operation. To trim a uniform-coloured border (e.g. solid white) instead, use Crop with measured coordinates.
Part of: Turn a logo into a clean transparent PNG
Key the background out, then trim — trimming first leaves the halo you were trying to remove.
- 1 Background Key out the white, or swap it for transparency
- 2 Auto-trim Crop the now-empty border away
- 3 Feather edges Soften a hard-keyed edge so it composites cleanly
- 4 Add outline Add a contrasting outline if it will sit on photos
- 5 Transparency checker Confirm no near-white pixels survived
Part of: Tidy up a scan or a photographed document
Deskew before cropping, or the crop keeps the tilt and cuts a corner off.
- 1 Rotate by angle Straighten it by a fraction of a degree
- 2 Perspective Pull a photographed page back to rectangular
- 3 Auto levels Make the paper white and the ink black
- 4 Auto-trim Cut the desk out of the edges
- 5 PNG to PDF Bundle the pages into one document