🖼️ Image & File

Compress PDF

Reduce your PDF file size by re-rendering each page at lower image quality. Download the compressed PDF — nothing leaves your browser.

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Click to upload or drag & drop a PDF

Single PDF file — max 50 MB recommended

How compression works

Each page of the PDF is rendered to a canvas using PDF.js at the chosen scale, then re-encoded as a JPEG at the selected quality level. The resulting images are assembled into a new PDF using pdf-lib. This method works best on PDFs with images or scanned content — text-only PDFs may not reduce much. Note: rendered PDFs lose selectable text and become image-only. Everything runs in your browser — no files are uploaded.

Why Compress a PDF?

Many email services cap attachments at 10–25 MB, and cloud storage platforms, job application portals, and government submission forms often have strict file size limits. A scanned document or image-heavy PDF can easily reach 20–50 MB — far too large to send or submit. Compressing the PDF to under the allowed size lets you share it immediately without needing to split it, pay for a cloud tool, or install software. This tool reduces file size by re-rendering pages at a lower image quality, which works particularly well for scanned PDFs where the visual difference is barely noticeable.

Key Features

  • Four compression levels: Low (best quality), Medium (recommended), High (smaller), and Max (smallest) to balance quality vs. size
  • Render scale options: Choose 1×, 1.5×, or 2× DPI for the rendering step to control output sharpness
  • Before/after stats: See original size, compressed size, and percentage reduction after processing
  • Visual size bar: Instant bar chart showing how much the file was reduced
  • Privacy-first: Uses PDF.js and pdf-lib in your browser — nothing is uploaded to any server

Real-Life Use Cases

  • Reducing a scanned invoice or contract from 15 MB to under 2 MB before emailing to a client
  • Compressing a photo-heavy portfolio PDF so it fits within a job application portal's 5 MB upload limit
  • Shrinking government or tax documents scanned on a home printer before submitting through an online portal
  • Reducing a travel brochure or product catalogue PDF for faster download on a website
  • Preparing a large scanned report for sharing via WhatsApp or messaging apps with attachment size restrictions

Who Can Use This Tool

Students, office professionals, accountants, freelancers, HR teams, and anyone who regularly handles scanned documents or image-heavy PDFs. It is especially useful for people who need to reduce file size quickly without installing software or paying for an online subscription.

Tips & Best Practices

  • Start with Medium compression — it usually achieves 40–60% reduction on scanned PDFs with minimal visible quality loss
  • For text-only PDFs (word-processed documents), compression may have little effect since text is already efficiently encoded as vectors
  • If the output looks blurry, try a higher render scale (2×) combined with a lower compression level for a sharper result at a slightly larger size
  • Check the compressed PDF on your device before sharing — zoom in to 100% on critical pages to verify text is still readable
  • For very large files (50+ MB), a desktop tool like Ghostscript will be faster and more powerful for advanced compression options

Frequently Asked Questions

How does browser-based PDF compression work?
This tool renders each PDF page to a canvas using PDF.js, then encodes the canvas as a JPEG at your chosen quality level. The resulting images are assembled into a new PDF using pdf-lib. This converts every page to an image, which works best for PDFs with scanned content or lots of images.
Why did my text-only PDF not reduce in size much?
PDFs containing only vector text and graphics are already very efficiently encoded. Re-rendering them as JPEG images (which this method does) may actually increase the file size for text-heavy PDFs. Image-based compression works best on scanned PDFs, image-heavy PDFs, or PDFs with many photographs.
Will the compressed PDF still have selectable text?
No. Because each page is converted to a JPEG image, the output PDF is an image-only document — text will not be selectable or copy-able. If you need to preserve selectable text, use a dedicated desktop tool like Adobe Acrobat, PDF24, or Ghostscript, which can compress metadata, fonts, and streams without rendering to images.
What compression level should I choose?
Low (90% quality) — minimal size reduction, best image quality. Medium (70%) — good balance, recommended for most cases. High (50%) — noticeable compression artifacts but significantly smaller. Max (30%) — smallest file, visible quality loss. Start with Medium and increase only if more reduction is needed.
Is there a file size limit?
There is no hard limit, but processing is done entirely in your browser so very large PDFs (50+ MB or 100+ pages) may be slow or cause the browser tab to run out of memory. We recommend keeping files under 50 MB. For very large files, a desktop tool like Ghostscript or Adobe Acrobat will be faster and more reliable.
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