What it is good for
Use it whenever something flat was photographed from the side: a receipt on a table, a printed page, a whiteboard after a meeting, a poster, a painting on a wall, a laptop screen, a shop sign or the front of a building. The result looks as if you had stood directly in front of it.
It is pure geometry, a conventional edit with no model. It works on any flat, four-cornered surface, whatever is printed on it.
Screens photographed at an angle are a common case too: a slide on a projector, a chart on a monitor, a menu board behind a counter.
Placing the corners
The four handles start inset 8 percent from the photo's corners, as a first guess. Drag each one onto a corner of the thing you want to flatten. Zoom in to place them precisely, because a handle a few pixels off makes an edge slightly crooked in the result.
If a corner is hidden, by a hand holding the page or something on top of it, place the handle where the corner would be, following the lines of the two edges that meet there. Curled pages are trickier: the tool assumes the surface is flat, so a bend in the paper stays bent.
Keep each handle in its own corner so the lines between them do not cross. A crossed shape gives a twisted result.
Choosing the output size
By default, the output size is worked out from the shape you marked. That keeps the proportions close to the original object. For documents, pick A4 or Letter so the page comes out at the right shape for printing or filing. Square suits artwork, tiles and record covers.
The warp is applied at full resolution with bilinear sampling, which keeps text and lines smooth. Parts of the photo outside your four corners are left out of the result.
For a building, mark four points on one flat face of it, such as the corners of the front wall. Parts that stick out, like balconies or a porch, will still lean, because they are not on that flat surface.
Taking a photo that corrects well
Get as close to straight-on as you can before you press the shutter. Every degree of angle means the far side of the object is captured with fewer pixels, and correcting it stretches those pixels. Even light helps too, since a shadow across a page stays after flattening. If the corrected document looks dull, Photo enhancer or Auto colour correction can brighten the paper afterwards.
What it will not do
- It assumes a flat surface; curled pages and curved screens stay curved.
- Strong angles stretch the far side, which can look softer after correction.
- Anything outside the four corners is not included in the result.
- It does not read text or clean up a scanned page; it only changes the geometry.
Devices and downloads
No download — ordinary image arithmetic. It is a geometric warp with no model, so WebGPU and WebAssembly are not involved. The full-resolution photo is processed in this tab when you apply.
Instant edit: Ordinary image arithmetic. No model, no download, works in any modern browser. See what is stored on this device.
Step by step
- Open the photo. Drop, paste or choose the angled shot.
- Drag the four handles. Place each one exactly on a corner of the flat object.
- Pick an output size. Keep the size from your corners, or choose A4, Letter or square.
- Apply and export. Check the straightened result, then save it.
Questions about perspective corrector
How do I straighten a document photographed at an angle?
Drag the four handles onto the page's corners, choose A4 or Letter, and apply. The page is flattened into a straight-on rectangle.
What if one corner of the page is covered?
Place that handle where the corner would be, continuing the two edges that meet there.
Will it flatten a curled or bent page?
No. It treats the surface as flat, so any curve in the paper remains after correction.
Why does the far side look softer after correcting?
That side was captured with fewer pixels because it was farther away, and flattening stretches them. Shoot closer to straight-on for sharper results.