PDF Compressor
Reduce PDF file size without losing quality. Three compression levels. Runs in your browser — no upload, free.
Drop PDF here or click to browse
Supports PDF files
About PDF Compressor
Large PDF files cause problems across the board: email systems reject attachments over a few megabytes, government and HR portals cap upload sizes, and sharing via messaging apps compresses images and degrades quality. The PDF Compressor reduces file size by recompressing embedded images and eliminating redundant internal data structures — often achieving 50–80% size reduction on scan-heavy documents while keeping text and vector graphics crisp.
The tool offers three compression levels to suit different use cases. Light compression preserves near-original image quality while removing internal redundancies — ideal for text-heavy PDFs with minimal images. Balanced compression recompresses embedded images at a high-quality JPEG setting, producing good results for most mixed-content documents. Aggressive compression maximizes size reduction for heavily image-laden files, at the cost of some image sharpness — appropriate when file size is the priority over pixel-perfect reproduction.
All compression runs locally in your browser using pdf-lib and the Canvas API. This is especially important for sensitive documents: scanned passports, medical records, financial statements, legal contracts — all stay on your device. You see exactly how much space is saved before downloading the result.
How to Use PDF Compressor
- 1Click "Upload PDF" and select the PDF file you want to reduce in size.
- 2Select the compression level — Light, Balanced, or Aggressive — based on your quality needs.
- 3Click "Compress" and wait for the browser to process the document locally.
- 4Review the before/after file size comparison to see how much was saved.
- 5Click "Download" to save the compressed PDF to your device.
Use Cases
- →Shrink a large PDF to meet an email attachment size limit (typically 10–25 MB)
- →Compress scanned documents before uploading to a government, HR, or medical portal
- →Reduce a PDF portfolio or presentation for faster web download and sharing
- →Batch-compress invoices or reports to reduce storage costs in a file management system
- →Compress a scanned book, manual, or magazine to reduce its archive footprint
- →Prepare PDF submissions for online application portals with strict file size limits
Tips
- ✓Balanced compression is the best starting point — it handles most documents well
- ✓Images embedded in PDFs benefit most from aggressive compression; text rendering is unaffected
- ✓For text-only PDFs (no images), light compression removes internal overhead with zero quality impact
- ✓If the result is still too large after aggressive compression, try splitting the PDF into smaller parts
- ✓Scanned documents (image-only PDFs) see the biggest size reductions from compression
- ✓Always keep the original uncompressed file — compression is lossy for image-heavy documents
Frequently Asked Questions
The compressor re-encodes images inside the PDF at lower quality and applies stream compression. Text and vector graphics are not affected — only embedded bitmap images are reduced.
Low: fastest, minimal size reduction, highest image quality. Medium: balanced (recommended for most documents). High: maximum size reduction, lower image quality.
No. All compression happens entirely in your browser using PDF-lib. Your file never leaves your device.
PDFs that contain mostly text and vector graphics have very little image data to compress. Size reduction only applies to embedded raster images.
Password-protected PDFs cannot be processed — you will see an error. Standard PDFs (including PDF/A) work fine.
There is no enforced limit — the tool is bounded only by your browser memory. For most documents (under 100 MB), compression completes in a few seconds.