Image Straightener

Level tilted photos with a grid and fine angle; choose expanded or cropped canvas and export PNG.

Level a tilted photo or scan by eye. This is manual fine rotation, not automatic deskew, perspective correction or text recovery. JPEG / still 8-bit PNG, up to 10 MiB and 4 million pixels.

Choose image to straighten

Fine rotation angle (degrees)

−15 to +15 in 0.1° steps. Positive is clockwise.

Canvas and edge policy

Exposed background

Show alignment grid (not exported)

Limits and a safer workflow

First fix large sideways/upside-down rotations with Rotate & Flip Image. Then level here and inspect letters, borders and corners at full size. Full image adds canvas around the rotated picture; Original canvas deliberately loses rotated edges. Output is limited to 6 million pixels and 8,192 pixels per side. This does not remove perspective, undo blur or reconstruct missing content. Browser color/EXIF decoding can vary, so inspect the saved PNG in its intended app. Cancel or any file/setting change prevents stale output from becoming downloadable.

This tool runs entirely in your browser. Your data is never uploaded, never stored, and never leaves your device.

Manually level a JPEG or still PNG with fine-angle rotation, an alignment grid and an explicit expanded-canvas or cropped-edge policy; export full-resolution PNG locally.

How to use it

1Choose an image or load the tilted-line example.
2Set a −15° to +15° angle, canvas policy and background; inspect the grid preview.
3Create the PNG and inspect its saved edges and text before sharing.

Example

Input: 320 × 220-pixel sample Clockwise angle: 5° Canvas: Full image
Output: 338 × 248-pixel PNG Expanded canvas, no alignment grid in the file

The sample lines were drawn at −5°. Rotating +5° levels them approximately; browser resampling can soften their edges.

What happens to your data

Image content is decoded, rendered and exported locally without upload. Fine rotation resamples pixels and does not preserve original metadata or encoding. Grid guides are not exported.

Last updated October 2026

Straighten an image when a horizon, scanned line or document edge is slightly tilted. Use the alignment grid and a fine angle from −15° to +15° to level it manually, then choose whether the output keeps the full rotated picture or intentionally crops it to the original canvas.

The preview shows the chosen canvas dimensions before you export a full-resolution PNG. Grid lines are viewing guides only and never appear in the download. This is a focused manual leveling tool, not automatic deskew, perspective correction, OCR, deblurring or recovery of missing image content.

How it works

Choose one ordinary JPEG or still 8-bit PNG up to 10 MiB, 4 million decoded pixels and 8,192 pixels per edge. File structure is checked before a browser image decoder reads it. Animated PNG, SVG and unsupported compound or malformed files are refused. The decoder can apply EXIF orientation; source and output dimensions refer to the decoded displayed pixels. Color management and decoding can differ among browsers, so the saved output should be inspected in its intended application.

Set the angle with a numeric field or a 0.1-degree slider. Positive angles rotate clockwise, negative angles counterclockwise. The range is intentionally limited to small alignment corrections. For sideways or upside-down images, use Rotate & Flip Image first; quarter-turn rotation and fine leveling solve different jobs.

Full image mode expands the canvas around the rotated source. For width w, height h and angle a, its integer size is ceil(|w cos(a)| + |h sin(a)|) by ceil(|h cos(a)| + |w sin(a)|). No source corner is deliberately cropped, although arbitrary-angle rotation necessarily resamples pixel edges. At zero degrees, dimensions remain exactly the source dimensions. Original canvas mode retains the original width and height and deliberately discards portions rotated outside that boundary. It does not promise an edge-to-edge picture without background corners.

Exposed regions can be transparent, white or black. Existing transparent areas are composited against that chosen background too. Output is limited to 6 million pixels, 8,192 pixels per side and 32 MiB. The on-page preview is scaled to fit the interface; the PNG export uses the full selected canvas, not a screenshot of that preview. The grid is a separate overlay and is not part of the exported canvas.

Fine-angle rotation uses browser Canvas resampling. Text and high-frequency detail can soften, and PNG output may be larger than the source JPEG. Original metadata, color-profile containers, print-density tags and encoding are not preserved. PNG avoids an additional lossy JPEG encoding step, but that does not make rotation a lossless transformation. Start with the best original and avoid repeatedly straightening previously exported copies.

Changing a file or rendering setting removes the previous download. Clear releases the decoded source and temporary download link; Cancel prevents a late asynchronous result from becoming downloadable, although work already running locally may finish. Turning the non-exported grid on or off does not change the exported image. File contents remain local; surrounding website resources and anonymous usage events may still access the network.

Worked example: Level tilted sample lines

Input: 320 × 220-pixel sample Clockwise angle: 5° Canvas: Full image
Result: 338 × 248-pixel PNG Expanded canvas, no alignment grid in the file

The sample lines were drawn at −5°. Rotating +5° levels them approximately; browser resampling can soften their edges.

Common use cases

Leveling a slightly tilted photo horizon with visible grid guides
Manually aligning scanned rows before a later OCR step
Choosing explicitly between extra canvas and cropped rotated edges
Exporting a corrected still image without uploading its content

Frequently asked questions

Does this automatically deskew my scan?＋

No. You choose the angle manually using a grid and preview. The tool does not infer text baselines or decide whether a document is straight. Check several lines, not only one short edge.

How can I straighten a photo without cutting off its corners?＋

Choose Full image — expand canvas. The canvas grows around the rotated image instead of deliberately cropping source corners. You will see exposed transparent or colored background around some edges.

What does Original canvas do?＋

It keeps the original decoded width and height. Source content rotated beyond that rectangle is discarded. Background corners can still appear, so it is not an automatic crop-to-fill or perspective correction.

Are the grid lines included in the download?＋

No. The grid is an interface-only overlay. The exported PNG contains the rotated image and selected background, but not the grid.

Is fine-angle image rotation lossless?＋

No. Arbitrary-angle rotation resamples pixels, which can soften small text and edges. PNG avoids another lossy JPEG encoding stage, but metadata and original encoding are not retained. Use the original file and avoid repeated editing passes.

Why is the exported PNG larger than the JPEG?＋

PNG and JPEG compress images differently, and an expanded canvas adds pixels. File size reduction is not this tool’s goal. Inspect the result first, then use the appropriate image compressor if a smaller delivery copy is needed.

Can I correct a sideways page or a photographed page’s perspective?＋

Use Rotate & Flip Image for quarter-turn orientation. This tool only performs small planar rotation; it cannot remove keystone perspective, flatten curved paper, restore blur or reconstruct missing corners.

Are my photos uploaded or stored?＋

The image decoder, preview and export operate in the current browser page with no content upload or saved tool history. Clear releases its temporary state; files you already downloaded remain on your device. Normal website assets and anonymous usage events may still use the network.