Document Scan Compressor

Document scan compression is the process of reducing the file size of scanned document images while preserving text legibility. Unlike photo compression, document scans contain high-contrast text, fine lines, and sharp edges that are particularly sensitive to compression artefacts. Our document scan compressor solves this by applying an unsharp mask filter before compression — enhancing text edges so they remain crisp even at lower quality settings. The result is a file that is significantly smaller than the original scan but still fully readable, suitable for PDF embedding, email delivery, and official submissions.

1. 1Upload Your Scanned Documents: Drag and drop or click to select any scanned document image — JPEG, PNG, TIFF, BMP, or WebP. You can upload multiple pages for batch processing. The document scan compressor accepts any resolution or original file size.
2. 2Configure Sharpening & Output Settings: Choose your sharpening level (Standard is recommended for most scans), output format (JPEG for colour scans, PNG for black-and-white text), and resolution preset (Print 300 DPI for PDF-ready output). All processing happens locally in your browser — your documents never leave your device.
3. 3Download Your Compressed Scans: Each result shows the original size, compressed size, reduction percentage, sharpening applied, and output dimensions. Download individually or as a ZIP archive for batch jobs.

• Unsharp Mask Sharpening: A 3×3 Gaussian blur is computed and subtracted from the original (scaled by the sharpening amount) — enhancing text edges and fine lines before compression reduces them.
• Resolution Scaling: Scans larger than the selected DPI preset are scaled down proportionally. Screen (96 DPI) reduces large scans to web-display size; Print (300 DPI) preserves full print-quality resolution.
• Format Compression: JPEG compression removes colour information the eye is least sensitive to — ideal for colour scans and photos. PNG lossless compression is better for black-and-white text documents where every pixel matters.
• Metadata Stripping: Canvas re-encoding removes all embedded EXIF metadata, GPS coordinates, and scanner model information — reducing file size and protecting privacy.

For most scanned documents, use Standard sharpening, JPEG format, and Print (300 DPI) — this produces PDF-ready output that is 60–80% smaller than the original scan with fully legible text. Use PNG format for black-and-white text-only documents where lossless compression is preferred. Use Strong sharpening for faded or low-contrast scans from older documents. Use Email (150 DPI) for scans that only need to be readable on screen and in email.