Background Eraser

The five tools, when to use which

• Pick bg colour: click any background spot to add its colour as a sample. Add as many as you need (e.g., one for the wall, one for the shadow). Then run Auto erase.
• Click-fill: click any region — the connected patch of that colour gets cleared. Perfect for one-off stray patches the auto pass missed, like a corner of bedsheet visible behind a shoulder.
• Erase brush: hold and drag to manually paint away pixels. Large brush for bulk, small brush for hairlines and earlobes.
• Restore brush: painted too much? Drag to bring the original pixels back. The original image is kept in memory so restore is always lossless.
• Rect erase: drag a rectangle to wipe everything inside it. Best for watermarks, timestamps, or removing a person standing behind your subject.

Every action is undoable — the editor keeps the last 25 states. Resetbrings you back to the original photo without losing the loaded image, so you can try a different approach without re-uploading.

Auto-erase algorithm

Auto-erase samples the pixel colours at the four corners and four edge midpoints (or uses the colours you picked in Pick bg colour mode). It runs a connected flood-fill from the canvas border inward — every pixel within tolerance of a sample gets cleared, but the fill stays connected so same-colour pixels inside the subject (white shirt, grey hair) are left intact. Pixels already cleared by manual edits are treated as background, so the fill keeps walking through them — meaning you can erase a tricky edge by hand and then run auto to mop up the rest.

A passport-photo workflow

1. Upload a clear photo on a plain wall.
2. Hit Auto erase. The bulk of the wall disappears.
3. Use Click-fill on any leftover patches (around hair, under chin).
4. Switch to the Erase brush (size ~12) to clean hair edges.
5. If you nicked the face, Restore brush brings those pixels back.
6. Pick White under "Replace background with", hit Render download and grab the JPG.
7. For a govt-form size and KB cap, run the result through the Govt Form Photo Formatter.

Good photos vs hard photos

• Easy: studio passport shots, product photos on white seamless, screenshots with a flat backdrop.
• Workable: selfies against a plain wall, profile photos, ID-card mugshots — usually auto + a couple of click-fills.
• Hard: outdoor photos with sky + trees, hair against patterned backgrounds, anything where the subject and the background share a dominant colour — expect heavy brush work.

Privacy and what leaves your device

Nothing. The image is read by your browser using FileReader, pixels are processed on a <canvas> element in JavaScript, and the result is downloaded back to your machine. No server upload, no third-party API, no tracking of the image. Close the tab and the photo is gone.