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Compress a PDF,
for free.

Two modes: Smart Compress keeps your links and text exactly as they are. Max Compress rasterises every page for the same 50-70% size reduction you see on competing tools - your choice.

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Private Local PDF Processing: Your files never leave your device and are never uploaded or saved. Disconnect your internet to test-this page works 100% offline.

Compress PDF

Upload a PDF, pick a mode, set your quality, and compress.

Drop a PDF here, or click to browse
One file at a time
75%

How it works

  1. Upload your PDF. Works on any PDF - scanned documents, Word exports, contracts, photo books.
  2. Choose a mode. Smart Compress recompresses embedded images and keeps everything else intact. Max Compress re-renders every page as an image for the deepest size reduction (like most online tools do).
  3. Set the quality. 75% is a good default. Go lower for maximum shrinkage, higher if fine print needs to stay sharp.
  4. Compress. Everything runs in your browser - no upload, no waiting. The result downloads automatically.

Understanding PDF File Bloat & Compression

PDF files often grow to unwieldy sizes (10MB to 50MB+) due to three primary factors: uncompressed high-resolution image scans, embedded vector font subsets, and hidden metadata streams. Understanding how compression works helps you choose the optimal settings for your documents.

Smart Compress vs. Max Compress: Technical Breakdown

Traditional cloud converters force every PDF through a heavy rasterization pipeline. FileSwift provides two distinct mathematical engines depending on your document requirements:

  • Smart Compress (Object-Level JPEG Quantization): Traverses the PDF internal object tree using pdf-lib, extracts embedded image streams (DCTDecode), and re-encodes them at your chosen quality setting. Vector line art, text glyphs, hyperlinks, digital signatures, and PDF bookmarks remain 100% vector and interactive.
  • Max Compress (Canvas Page Rasterization): Uses pdf.js and HTML5 Canvas to render each page at 150 DPI into compressed JPEG tiles, then re-assembles them into a fresh PDF using jsPDF. This strips out all complex structural bloat and guarantees 50% to 70% size reduction on heavy scanned files.

Compression Mode Benchmark & Recommendations

Document TypeTypical Raw SizeSmart Compress OutputMax Compress OutputRecommended Mode
Scanned Paper Document (A4)8 MB - 25 MB3 MB - 6 MB600 KB - 1.2 MBMax Compress (70%)
Resume / CV (Word Export)2 MB - 5 MB300 KB - 600 KB400 KB - 800 KBSmart Compress (80%)
Contract / Legal Document5 MB - 15 MB800 KB - 2 MB1 MB - 2 MBSmart Compress (75%)
Photo Album / Presentation20 MB - 80 MB8 MB - 15 MB3 MB - 6 MBMax Compress (65%)

How to Get Your PDF Under Strict Portal Limits (e.g. 500 KB or 1 MB)

When applying for government portals (like CPNS SSCASN, BPJS), university admissions, or corporate job boards, files over 1 MB or 500 KB are often rejected immediately. Here is the recommended workflow to hit tight limits:

  1. Start with Smart Compress at 75% to preserve text crispness.
  2. If the file is still above the limit, switch to Max Compress at 70%.
  3. If further reduction is needed for multi-page documents, use the slider to set quality to 55%-60%, which cuts file size substantially while keeping 10-point text legible.

Frequently Asked Questions

What is the difference between Smart Compress and Max Compress?

Smart Compress works at the PDF object level - it finds embedded images and recompresses them at your chosen quality while leaving text, links, annotations, and form fields completely untouched. Max Compress re-renders every page as a JPEG image (the same approach most online PDF compressors use), achieving 50-70% reduction on most files but producing a flat, image-only PDF where text and links no longer work.

Which mode should I use for official contracts and job applications?

Use Smart Compress for resumes, contracts, government forms, or any document with clickable links and text that needs to remain searchable by ATS (Applicant Tracking Systems). Use Max Compress when you have a scanned paper document or photo-heavy PDF where getting the smallest file size is the top priority.

Is it safe to compress confidential financial or legal PDFs here?

Yes. FileSwift is 100% client-side. The entire compression process executes inside your local web browser tab using WebAssembly and JavaScript. No document data is ever transmitted across the internet to external servers. You can even disconnect your Wi-Fi or turn on Airplane Mode to verify.

My PDF is already small - what happens if I run it through anyway?

Smart Compress will detect this and return the original file without modification - the output will never be larger than what you uploaded. Max Compress will still reduce the file because it re-renders pages at a controlled resolution regardless of the source.

Can I compress password-protected PDFs?

Encrypted PDFs must first be unlocked before they can be compressed. You can use our free Unlock PDF tool to remove the password restrictions first, and then compress the resulting file.