PDF Enhancer
Three scientific approaches to scan enhancement. Pick your mode, upload, done.
Drop your scanned PDF here
Old books, photographed pages · Max 50MB
Enhancement Mode
AI Clean Mode
Neural network removes stains, shadows, and sharpens text. Best for severely degraded scans.
Mode Comparison
Standard
Fast, reliable. Best for most scanned books with clean backgrounds.
Retinex
Simulates human vision. Removes yellowing naturally. Film-like quality.
Guided Filter
Cleanest background. No halos or artifacts. Best for heavy shadows.
AI Clean
Neural network removes stains, shadows, and sharpens text. Best for severely degraded scans.
OCR Render
Removes background, renders only text as vector. Perfectly clean output.
How to use
- Upload your scanned or faded PDF document.
- Select an enhancement mode (Standard, Retinex, Guided, or AI Clean).
- Adjust fine-tuning sliders for contrast, sharpness, and brightness.
- Wait for the AI pipeline to process and repair your text.
- Download your restored, high-quality PDF.
Why use this tool?
Old Book Restoration
Specially designed algorithms to fix yellowing, aging, and stains in scanned books.
Text Stroke Repair
Uses Deep Learning to repair broken characters and amplify faded text strokes.
EDSR 4× Super-Resolution
Upscale low-resolution scans to 4K quality using advanced neural networks.
Advanced Shadow Removal
Lift shadows and normalize backgrounds for a perfectly clean, printable result.
OCR Rendering
Convert flat scans into searchable vector text while preserving original diagrams.
Frequently asked questions
How does the AI PDF Enhancer work?▼
Can it fix extremely old, faded documents?▼
Is my data private during processing?▼
What is the 'Guided Filter' mode?▼
Does it support multiple languages for OCR?▼
About PDF Enhancer
Enhance your PDF documents online for free. Improve quality and add features to your PDF files. This free online tool runs entirely in your browser — no files are ever uploaded to our servers, ensuring your data stays private and secure. No registration, no watermarks, no limits.