PDF Compressor
Reduce PDF file size with lossless compression. Remove metadata (author, timestamps, XMP), optimize object streams, and re-encode structure — all without touching content, fonts, or images. 100% client-side — your files never leave your browser.
Drop a PDF here or click to upload
Removes metadata and optimizes PDF structure — 100% client-side
How to use
- 1 Drop a PDF onto the upload area — the file name, page count, and original file size are displayed immediately.
- 2 Toggle the options you need: "Remove metadata" strips author, creator, and timestamps; "Use object streams" packs objects for smaller files.
- 3 Both options are lossless — they reduce file size without affecting page content, fonts, or image quality.
- 4 Click "Optimize PDF" — the tool processes the file entirely in your browser using pdf-lib.
- 5 Download the optimized PDF and review the before/after size bar to see exactly how much space was saved.
Key features
- Lossless optimization only — strips metadata and uses object streams without touching content, fonts, or images
- Removes Author, Creator, Producer, timestamps, and XMP metadata streams embedded by editing tools
- Before/after size bar shows exactly how many bytes were saved after optimization
- 100% private — your PDF never leaves the browser; ideal for confidential or legal documents
What does PDF compression do?
PDF "compression" covers a range of techniques to reduce file size. This tool performs lossless structural optimization: it re-encodes the PDF object table, removes embedded metadata (author, creator, timestamps, keywords), and optionally packs objects into compressed streams — all without touching page content, fonts, or images.
The result is most noticeable on PDFs that carry significant metadata bloat or were generated by tools that write verbose object structures (e.g. office suites, CAD software, or export pipelines). It will not dramatically reduce PDFs that are already well-optimized or whose size is dominated by high-resolution images — for those, consider compressing the images before creating the PDF.
Unlike many "PDF compressor" services that upload your documents to a remote server for processing, this tool runs entirely in your browser using pdf-lib. Your document never leaves your device — ideal for confidential business, legal, or personal PDFs.
Lossless vs. lossy compression
| Type | Quality loss | Typical reduction | Best for |
|---|---|---|---|
| Lossless (this tool) | None | 1–15% | Metadata-heavy PDFs, bloated exports |
| Lossy image resampling | Slight | 20–70% | PDFs with high-res photos (use Ghostscript or Adobe) |
| Aggressive (Ghostscript) | Moderate | 50–90% | Archiving, email, maximum size reduction |
Common Use Cases
Strip tool fingerprints
Remove Author, Creator, and Producer fields that reveal which software generated the PDF.
Reduce email attachment size
Lossless optimization can meaningfully reduce PDFs that carry large metadata blocks or were generated by verbose tools.
Minimize legal document metadata
Remove timestamps and author names before sharing contracts or NDAs externally.
Clean up exported PDFs
Many office tools embed extensive XML metadata blobs. Re-saving strips this bloat without affecting content.
Pre-process before merging
Optimize each PDF individually before merging to keep the combined file as small as possible.
100% private
Your document never leaves your browser — ideal for confidential business or legal PDFs.
What metadata is removed?
Document Info Dictionary
Title, Author, Subject, Keywords, Creator, Producer, CreationDate, ModDate — standard PDF metadata visible in "Properties" dialogs.
XMP metadata streams
Extended metadata packets embedded as XML — often added by Adobe tools, export pipelines, and creative apps.
Redundant cross-reference data
Incremental update sections added by editing tools. Object streams pack these more efficiently.
Frequently Asked Questions
Does PDF compression reduce image quality?
This tool performs lossless compression only — it never re-encodes images, fonts, or page content. The file size reduction comes from removing embedded metadata (author, creator, timestamps, XMP streams) and optimizing the PDF's internal object structure. If your PDF is large because of high-resolution images, consider compressing those images before creating the PDF for maximum savings.
How much can I reduce my PDF file size?
Typical savings range from 1% to 15%, depending on how much metadata and bloat the PDF carries. PDFs exported from office suites, CAD software, or tools that embed large XMP metadata streams often see the biggest reductions. PDFs that are already well-optimized or image-heavy will see minimal change from structural optimization alone.
What metadata is removed from my PDF?
When you enable "Remove metadata", the tool strips the Document Info Dictionary (Title, Author, Subject, Keywords, Creator, Producer, CreationDate, ModDate) and any embedded XMP metadata streams. This is useful for removing software fingerprints, timestamps, and author names before sharing documents externally. The option is enabled by default.
Is it safe to upload confidential documents?
Yes — this tool runs 100% in your browser. Your PDF is never uploaded to any server, stored, or transmitted. All processing using pdf-lib happens locally on your device. This makes it ideal for confidential business, legal, or personal documents that you cannot risk sending to a third-party service. No account or registration is required.
What's the difference between lossless and lossy compression?
Lossless compression reduces file size without any change to the visible content — text, images, and layout remain identical. This tool is lossless. Lossy compression reduces file size by discarding some image detail or re-encoding content at lower quality (like JPEG compression). Lossy tools (like Ghostscript) can achieve 50-90% reduction but may introduce visible artifacts. Use lossless when quality matters; use lossy when maximum size reduction is the priority.