Compress PDF Online Free
Reduce your PDF file size without losing quality. Strip metadata, optimise structure, and download a lighter file in seconds — completely free.
Drop files here or tap to browse
Max 20 MB · .PDF files accepted
How to compress a PDF online
Upload Your PDF
Drag and drop your PDF into the upload area or click to browse. Files up to 20MB are supported.
Click Compress PDF
Hit the button and our engine strips metadata, optimises cross-reference streams, and reduces file overhead.
Download Instantly
Your compressed PDF downloads automatically. No watermarks, no sign-up, no waiting.
Why use TryMyPdf to compress PDFs?
No Quality Loss
Content, fonts, and images are preserved. We optimise the file structure, not your data.
100% Free
Compress as many files as you need. No account, no subscription, no limits.
Secure & Private
Files are processed over HTTPS and permanently deleted within 1 hour of processing.
Works Everywhere
Browser-based — works on Windows, Mac, Linux, and mobile without any software.
Frequently Asked Questions
How much will my PDF shrink?+
Results vary by content. PDFs with lots of metadata, embedded thumbnails, or redundant streams can shrink by 20–60%. Text-only PDFs with no metadata are already lean and may change minimally.
Will compression make my PDF look different?+
No. Our compressor optimises file structure and strips hidden metadata — visible content, fonts, images, and layout are completely untouched.
Can I compress a password-protected PDF?+
No. Remove the password first using our Unlock PDF tool, then compress the file.
Is there a file size limit?+
Yes — files up to 20MB can be uploaded. If your file is larger, try splitting it into parts first using our Split PDF tool.
Are my documents stored after compression?+
No. All uploaded and processed files are automatically deleted from our servers within 1 hour. We never read or share your documents.
File still too large after compressing? Split the PDF first to remove unneeded pages, then compress again. Or delete specific pagesyou don't need.
What is Compress PDF?
PDF compression reduces the file size of a PDF document by removing redundant internal data — without touching visible content. Metadata, hidden thumbnails, duplicate objects, and inefficient stream encoding can all add significant overhead to a PDF without contributing anything to its appearance or readability.
When should you use it?
Compress a PDF when it exceeds an email attachment limit (most providers cap at 10–25 MB), when an upload form rejects it due to size restrictions, when you want to save storage space in cloud services, or when transferring files over slow connections. Even a 30–50% reduction in size makes a practical difference.
How Compress PDF works under the hood
TryMyPdf's compressor analyses the PDF's internal cross-reference table and object stream structure. It strips hidden metadata such as author info, edit history, and embedded thumbnails. Redundant objects are removed and stream data is re-compressed using optimised DEFLATE encoding. Crucially, the compressor never re-samples or down-scales images — visible quality is always fully preserved.
Common use cases for Compress PDF
Email Attachments
Reduce a PDF below common email size limits (10 MB for Gmail, 25 MB for Outlook) so it sends without rejection or splitting.
Web Form Uploads
Many government portals, HR systems, and application platforms cap PDF uploads at 2–5 MB. Compression makes them submission-ready in seconds.
Cloud Storage Archiving
Compress old reports and documents before archiving to free up space in Google Drive, Dropbox, or OneDrive without losing any content.
WhatsApp & Messaging Apps
Messaging platforms cap file sizes strictly. Compress PDFs to share over WhatsApp, Telegram, or Slack without switching to file-sharing links.
Online Print Service Uploads
Online printers often limit upload sizes. Compress high-resolution PDF brochures or flyers before uploading to printing platforms.
Website Download Files
Compress PDF guides, reports, and white papers before publishing them as website downloads to improve load times and user experience.
LMS & eLearning Platforms
Learning management systems often limit resource uploads. Compress course PDFs, slides, and reading materials before uploading.
Audit & Compliance Filing
Many regulatory portals have strict document size caps. Compress financial reports and compliance certificates before submission.
Tips for best results
Split first for very large files
If your file exceeds 20 MB (our upload limit), use Split PDF to divide it into smaller sections first, compress each part, then merge them back using Merge PDF.
Remove unnecessary pages beforehand
Use Delete Pages to remove blank pages, cover sheets, or irrelevant appendices before compressing. Fewer pages means a smaller compressed output.
Compress once, not repeatedly
Running a PDF through the compressor multiple times provides diminishing returns. The first pass removes most redundant data — repeated passes add little further reduction.
Text-heavy PDFs compress less
PDFs consisting mostly of text are already lean by nature. The biggest gains come from PDFs with lots of embedded metadata, thumbnails, or unoptimised streams from design software exports.
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