Crop & Scan Documents Online – Free & Private
Our free document scanner lets you straighten, crop, and enhance photos of documents directly in your browser. Use Harris corner detection to automatically find document edges, correct perspective distortion with a homography transform, and download the result in colour, black & white, or high-contrast mode — all without uploading anything to a server.
How to Scan a Document
1
Upload Your Photo
Drop a photo of a document onto the upload area or click Upload Photo. Supports JPEG, PNG, WebP, and HEIC (iPhone).
2
Detect & Adjust Corners
Click Detect Corners to auto-find the document edges. Drag any of the four corner handles to fine-tune. A magnifier shows pixel-precise zoom while dragging.
3
Choose Colour Mode
Pick Color to keep original colours, B&W for a clean grayscale scan, or Hi-Con for maximum text readability.
4
Crop & Download
Click Crop & Download to apply perspective correction and save the straightened document image.
Why Use This Document Scanner?
- 100% private – all processing happens in your browser using the HTML5 Canvas API. Your documents never leave your device.
- Harris corner detection – automatically locates the best document contour so you rarely need to adjust manually.
- Pixel-accurate magnifier – a 3× zoom magnifier follows your finger/cursor when dragging corners for precise placement.
- Perspective correction – homography transform straightens even angled or skewed document photos.
- Three enhancement modes – Color, B&W, and High-Contrast to suit any document type.
- HEIC support – iPhone HEIC/HEIF photos are automatically converted to JPEG before processing.
- Free & unlimited – no signup, no watermarks, no limits.
Frequently Asked Questions
Yes, 100% free with no usage limits. No account or payment information is required.
No. All scanning and processing happens entirely inside your browser. Your images are never sent anywhere.
The tool uses a Harris Corner Response approach on a grayscale, edge-enhanced version of your photo to find strong corners. It then picks the quadrilateral contour that best encloses the document area.
Yes. Simply drag any of the four blue corner handles to the exact position you need. A 3× magnifier will appear to help you place each corner with pixel accuracy.
Use Color to preserve original photo colours (e.g. for ID cards or colourful diagrams). Use B&W for clean grayscale scans of text documents. Use Hi-Con (High Contrast) for maximum text readability on documents with faint ink or uneven lighting.
Yes. HEIC and HEIF files are automatically converted to JPEG in your browser before processing. A loading indicator is displayed during conversion.
The cropped document is saved in the same format as the original photo (JPEG, PNG, or WebP). HEIC originals are saved as JPEG.