Compress PDF Online Free
Reduce PDF file size for email, upload and sharing — no upload, no account, fully private.
Compress PDF FreePDF files — low, medium and high compression levels, batch download as ZIP.
Compress PDF online free and reduce file size for email, uploads and sharing. Three compression levels let you balance size and quality. No upload — everything runs in your browser. No account, no limits.
Compress PDF online — reduce file size for email and upload
Large PDF files can slow down uploads, email sending and website performance. Compressing PDFs helps reduce file size while keeping text readable and images clear. PDF files can often be reduced by 50–90% depending on content and compression level — a 20 MB document can become 2–5 MB without any visible change in the text or layout.
This tool offers three compression levels. Low compression removes redundant objects and metadata with minimal quality impact. Medium compression downsamples embedded images to reduce size significantly — the right setting for most email attachments and business documents. High compression achieves maximum size reduction for files that must fit strict email size limits or be fast to upload.
All compression runs locally in your browser. Your PDF files are never uploaded to any server, never stored and never accessible to anyone else. Compress confidential documents, legal contracts, financial reports or any sensitive content without any privacy risk. No account is required — compress as many PDF files as you need, completely free.
Also try PDF Merge to combine multiple PDFs, PDF Split to extract pages, or PDF to JPG to convert pages to images.
- 1Upload your PDF files
Drag and drop one or more PDF files onto the upload area, or click to browse. All files are processed locally in your browser — nothing is uploaded to any server. Upload any number of PDFs in a single session.
- 2Choose compression level and compress
Select low, medium or high compression. Low: minimal quality change, modest size reduction (20–40%). Medium: best balance for email and sharing (40–70% reduction). High: maximum size reduction (50–90%) for strict size limits. Click "Compress All" to process all files in your browser.
- 3Download compressed PDF files
Each file shows the original size, compressed size and savings percentage. Download individually or click "Download All" for a ZIP archive. Compressed PDFs are ready to send by email, upload to any platform or share as a link.
When to compress a PDF
Compress PDF for email — fit attachment size limits
Gmail, Outlook and most email providers limit attachments to 10–25 MB. A scanned contract, a multi-page report or a presentation exported to PDF can easily exceed these limits. Compress the PDF to medium or high level — a 15 MB document becomes 3–5 MB, well within any email attachment limit. Smaller attachments also load faster in email preview on mobile.
Reduce PDF size for upload — portals, forms and CMS
Document portals, government forms, HR platforms and content management systems often enforce file size limits. Reduce PDF file size for upload to ensure your document is accepted without rejection. Medium compression preserves text sharpness and chart legibility while making the file significantly smaller.
Make PDF smaller for sharing — links and downloads
A PDF shared via a link loads faster and downloads faster if the file is smaller. Optimize PDF for sharing on Google Drive, Dropbox, Notion or any file-sharing platform — smaller files open faster on mobile connections and are less likely to time out on slow networks.
Shrink PDF for web — download links and embedded viewers
PDFs embedded in websites or served as download links add to page weight and increase server bandwidth costs. Compress PDF for web use to reduce download time and server load. A 10 MB press kit PDF compressed to 1.5 MB downloads 6× faster for every visitor.
Why this PDF compressor works
Three compression levels, privacy-first processing, and batch capability — built for document workflows.
Reduce PDF size while keeping text readable and images clear
The compressor applies image downsampling, stream compression and redundant object removal to shrink PDF file size. Three compression levels — low, medium and high — let you control the tradeoff between file size and document quality. Low preserves all visible detail; medium balances size and readability; high achieves maximum size reduction for documents where file size matters most. Text content remains fully selectable and searchable at all compression levels.
Your PDF files never leave your device
All compression runs locally in your browser using JavaScript and pdf-lib. No PDF file is uploaded to any server, transmitted over the network or stored anywhere. The tool works without an internet connection after the initial page load. This makes it safe for compressing confidential documents, legal files, financial statements, medical records and any content that cannot touch a third-party server.
Compress multiple PDF files in one session
Upload as many PDF files as you need — there is no batch size limit. All files are processed in your browser. Compression progress is shown per file. When all files are done, download them individually or use the "Download All" button to get a ZIP archive. Compress an entire document set or archive in a single session — no account, no upload queue, no waiting.
Questions about PDF compression
Yes — completely free. No account, no payment, no watermark, no daily limit. Compression runs in your browser on your device.
PDF files can often be reduced by 50–90% depending on content and compression level. A 20 MB document with embedded images can become 2–4 MB on high compression. Text-only PDFs see smaller reductions since they contain little image data.
Text content remains fully readable at all compression levels. Image quality inside the PDF is reduced on medium and high settings — embedded photos and graphics are downsampled to lower resolution. Low compression preserves all image quality with only modest size reduction.
Upload your PDF, select medium compression, click "Compress All" and download. Medium compression reduces most business PDFs by 40–70% — a 15 MB file becomes 3–5 MB, well within Gmail and Outlook attachment limits.
Yes. All compression runs locally in your browser. Your PDF files never leave your device — no server, no upload, fully private.
Yes. Upload any number of PDF files and click "Compress All". Download individually or use "Download All" for a ZIP archive.
Low: preserve image quality, modest size reduction. Medium: best for email and sharing — good quality, 40–70% smaller. High: maximum compression for strict size limits — text stays readable, images are lower quality.
Yes. Open the tool in Safari (iPhone) or Chrome (Android), upload PDF files, compress and download. No app required.
Ready to compress your PDF files?
Compress PDF Free