Compress PDF
Three rasterise tiers to shrink PDFs, with a before/after size check
Drag & drop files here
or browse files
Scans and image-heavy PDFs shrink the most - text PDFs, read the note first
About this tool
A scan too large to email, an upload form that rejects the file size - compressing PDFs is an everyday need. This tool works by "rasterised compression": pdf.js re-renders every page at the tier you pick and rebuilds them into a new PDF as JPEG images. Scans and image-heavy PDFs, which are mostly pictures, often shrink to a fraction of their original size.
Honest caveat: after rasterisation the text of a text-based PDF becomes an image and may look soft when zoomed, and the result is not guaranteed smaller - files that are already well optimised can grow. The before/after size and the savings percentage are shown as soon as it finishes, so you can switch tiers and retry with zero risk; the original file is never modified.
Features
- Three tiers - High (sharpest), Balanced (recommended), Strong (smallest)
- Instant before/after size comparison with the percentage saved
- Page-by-page progress; a typical document finishes in minutes
- Fully local processing - no upload, no signup, no watermark
- Read-only original: trying different tiers is risk-free
How to use
- Drop or select the PDF you want to compress
- Pick a tier: High for sharpness, Balanced (recommended), Strong for size
- Click Compress and wait for the page-by-page rendering
- Compare the sizes, download, or retry with another tier
Frequently asked questions
- The text looks blurry after compression - what can I do?
- Rasterised compression turns every page into an image, so text-based PDFs can look soft when zoomed. Switch to the High tier (higher DPI and quality) and compress again for a clear improvement; for documents with important small print, check each page after compressing.
- Why is the compressed file larger than the original?
- If the original PDF is already well optimised (mostly text and vectors), re-rendering it as JPEG adds size. The tool reports the change honestly when it finishes; for such files keep the original, or reduce the file size with the PDF Split tool instead.
- How well does it compress scanned documents?
- Scans and image-heavy PDFs are the best case: the pages are mostly photographs, and re-encoding them as JPEG usually cuts the size to a fraction with no visible difference. Start with the Balanced tier and adjust from there.
- Do I need an account to compress PDFs here?
- No. The tool is free with no membership, usage limits or watermark on the output. Compression runs in your browser and nothing is uploaded, so it even works offline.