A 20 MB PDF can become a real obstacle: too slow to email, impossible to upload to a form, and awkward to share via messaging apps. The good news is that in most cases you can cut that size by 50–80% with no visible difference in quality.
A PDF can be heavy for several reasons:
There are three main approaches, each with its own strengths:
Converts each page to a compressed JPEG image and rebuilds the PDF. Achieves reductions of up to 80%. Text is no longer selectable, making it ideal for final documents, scanned contracts, or presentations.
Tools like Adobe Acrobat Pro analyze the PDF and compress only the embedded images without touching the text. Text remains selectable. Compression is lower (20–50%) but the document retains all its features.
The most powerful option for technical users: gs -sDEVICE=pdfwrite -dPDFSETTINGS=/ebook -dNOPAUSE -dBATCH -sOutputFile=output.pdf input.pdf. Use /ebook for good compression, /screen for maximum, /prepress for minimum.
Most online PDF compression tools send your document to an external server for processing. This raises privacy concerns — especially with contracts, invoices, or confidential documents.
ComprimirPro processes your PDF 100% in your browser. Your files never leave your device — no server, no upload.
Drop your PDF, adjust quality, and download in seconds. No sign-up, no limits.
⚡ Compress my PDF| Quality | Estimated reduction | Best for |
|---|---|---|
| 80–95% | 20–40% | Fine text, print-ready presentations |
| 60–75% | 40–60% | General use — email, online forms ✅ recommended |
| 40–55% | 60–70% | Scanned documents, large files |
| 20–35% | 70–80% | Only when size is critical and quality is secondary |
For most use cases — emailing a contract, uploading to a portal — 70–75% quality is the sweet spot. The result is visually indistinguishable from the original and weighs half as much.
⚠️ Text will not be selectable. When pages are converted to images, the resulting PDF doesn't allow copying text, internal searching, or screen reader interpretation. If the document needs to be read digitally or requires accessibility, use Adobe Acrobat or Ghostscript instead.
This is not an issue for:
It depends on the protection type. If the PDF is only protected against editing but can be opened without a password, compression is possible. If it requires a password to open, you'll need to unlock it first.
With image re-rendering, text becomes part of the image. If you use a high quality setting (70%+) and the text was legible to begin with, it will remain legible in the output. For technical documents with small typography, use 80%+ quality.
It depends on the content. A scanned PDF can be reduced by up to 80%. A native text-only PDF is already fairly optimized and might shrink 20–30%. PDFs with many uncompressed photos benefit the most.
It depends on the tool. ComprimirPro processes everything in your browser — your files are never sent to any server. Other tools do upload the file. For confidential documents, always use tools with local processing.