Straighten a tilted photo without losing the edges

The job

The photo is almost right but the horizon tilts a few degrees. Editors make this easy; a quick in-browser fix is easier. The question is what to do with the empty corners that appear when a rectangle rotates.

Two canvas modes

Fit rotated image expands the canvas so nothing is lost — the corners become transparent (or your chosen background). Fill canvas does the opposite: it crops to the largest rectangle still fully covered by the rotated image, so there are no empty corners but the edges are trimmed.

A 4000×3000 photo straightened by 3° in fill mode loses a thin band around the edges — usually the right trade for a final image. Fit mode is better when the whole subject must stay visible and you will crop later.

Limits

Angles −180° to 180°, output always PNG. For exact 90° corrections (a sideways phone photo), Rotate & Flip is the better tool — it remaps pixels losslessly instead of resampling. JPG input becomes PNG output here; convert afterward if you need a JPG.