How do I reduce PDF file size by 80% without losing quality?

PDF Legacy's smart compression analyzes image resolution and removes redundant data. Choose "High Compression" for maximum size reduction or "Lossless" for quality preservation — both free.

Why is my PDF still large after compressing?

PDFs with embedded fonts, high-res images, or scanned pages compress less. Try PDF Legacy's "Deep Compression" mode which optimizes images internally. For scanned PDFs, run OCR first then re-save.

Is there a free PDF compressor without file size limits?

PDF Legacy's core compression has no strict file size limit since it runs locally in your browser. Your hardware is the only constraint — compress 500MB PDFs if your device can handle it.

How do I compress a PDF for email attachment under 25MB?

Upload to PDF Legacy, select "Email Optimized" preset, and the tool auto-compresses to under 25MB while keeping text readable and images clear. Download and attach directly.

Will compression affect PDF/A archival compliance?

Standard compression may remove PDF/A compliance tags. If you need archival standards, compress first, then convert to PDF/A using our dedicated tool to restore compliance.

WorkspaceKnowledge Base

Edit & Optimize · Tool

Compress PDF files

Reduce file size without losing quality — choose your compression level

Upload

›

Configure

›

Download

Drop your PDF files to compress

Get smaller PDF files without visible quality loss
100% secure · Processed locally · Zero retention

Accepts:PDFScanned PDFMulti-pageLarge files

Files never stored · End-to-end encrypted

#HOW IT WORKS

How to compress PDF files

Three steps, no software to install. Documents are processed locally on your device.

Upload your PDF files

Drop one document or multiple PDF files at once. All PDF versions and scanned documents are supported.

Choose compression level

Select High, Medium, or Low compression, or pick specific targets for Web, Print, or Email attachments.

Download your compressed PDF

Download your optimized PDF immediately with reduced file size and preserved visual quality.

#WHY COMPRESS

PDF Legacy vs Cloud Compressors

Standard online compressors upload your private files to remote cloud servers. PDF Legacy shrinks PDFs 100% locally on your device.

FEATURE COMPARISONCloud Compressors

PDF LegacyRECOMMENDED

Processing location

Remote Cloud Server

100% In-Browser (Local)

File size limit

Capped at 15MB - 50MB

No Limit (Device Memory)

Document privacy

Files uploaded & logged

Zero upload / Zero retention

Vector & font retention

Rasterizes full page to image

Preserves vector graphics & font subsets

Compression speed

Slow upload & queue wait

Instant client-side execution

#WHY PDFLEGACY

Built for speed, privacy, and precision

Made for anyone reducing heavy PDF documents, scanned contracts, or presentations for email attachments.

Smart DPI Downsampling

Intelligently resamples high-resolution embedded images to 72, 150, or 300 DPI targets based on your exact display output needs.

Structure & Metadata Stripping

Removes hidden thumbnail streams, XML metadata tags, and orphaned revision history to shave unnecessary megabytes.

Font Subsetting Engine

Prunes unused glyphs from embedded TrueType and OpenType fonts while retaining 100% text readability across all PDF viewers.

Email Attachment Ready

Reduces bulky 100MB+ slide decks and contract scans under 25MB limits for seamless Outlook and Gmail sending.

Flate Stream Compression

Re-compresses PDF content streams with high-ratio Flate algorithms and object streams for maximum byte efficiency.

Zero Retention Privacy

Your sensitive audit reports and legal filings never leave your device. Zero cloud uploads, zero third-party telemetry.

#FAQ