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Compress PDF

Reduce PDF file size while keeping documents readable.

Reduce PDF sizeCompression optionsBrowser validationReview before sharing

A practical middle ground for most PDFs, uploads, and email attachments.

Higher compression may reduce image quality. Text-only PDFs may not shrink as much as image-heavy PDFs.

Compression Results

Compare original and compressed file size before downloading.

Status: idle

Original size

No file

Upload a PDF first.

Compressed size

Not ready

Shown after processing.

Size saved

Not ready

Original minus compressed size.

Reduction

Not ready

Moderate quality impact

File validation

Checks file type and size before processing to avoid unsupported uploads.

Compression controls

Choose low, balanced, high, or custom quality settings for the intended use.

Privacy-conscious flow

The current fallback validates PDFs in the browser and does not add backend storage.

Dynamic Compression Insights

Upload a PDF to estimate compression results.
Selected compression level: Balanced compression.
Image-heavy PDFs usually compress more than text-only PDFs.
Balanced or low compression is usually better when visual quality matters.
Metadata removal is enabled, which may slightly reduce size when supported.
Image downscaling is enabled, which can reduce image-heavy PDFs when supported.

How PDF Compression Works

PDF compression reduces file size by optimizing document data.

Image-heavy PDFs can often be reduced by lowering image quality or dimensions.

Metadata and unused data may be removed when supported.

Already-compressed PDFs may shrink only slightly.

Compression should preserve readability and document structure.

Compression Levels Explained

Low compression / best quality

Keeps visual quality higher. Best for print-ready or image-sensitive PDFs.

Small to moderate savings

Balanced compression

A practical middle ground for most PDFs, uploads, and email attachments.

Moderate savings

High compression / smaller file

Targets smaller file size. Images may become less sharp.

Best savings

Custom quality

Use the custom quality slider for more control when connected to a real compressor.

Depends on settings

Image Quality, Fonts, Metadata, and File Size Notes

Scanned PDFs are often image-heavy.
Image resolution has a major effect on file size.
Embedded fonts can increase PDF size.
Metadata usually adds a small amount of data.
Forms, signatures, annotations, and bookmarks should be preserved unless intentionally removed.
Password-protected PDFs may not compress unless unlocking is supported.

Common PDF Compression Examples

Compress a scanned PDF for email.
Reduce a 10 MB PDF below a 5 MB upload limit.
Compress a report for online submission.
Optimize a PDF portfolio.
Reduce image-heavy lecture notes.
Shrink a PDF for cloud storage.
Compress a PDF with minimal quality loss.

Work, School, and Document-Sharing Use Cases

Email attachments
Job applications
School submissions
Government forms
Client reports
Invoices and receipts
Scanned documents
Portfolios
Cloud storage
Website uploads

Privacy and Local Processing Notes

The current fallback validates files in the browser.
No account is required.
This page does not add backend storage or a server compression step.
If server or API compression is added later, disclose the upload and processing behavior clearly.
Use care with private documents, IDs, legal files, financial records, medical records, and confidential work files.
Only compress PDFs you own or have permission to modify.
Review important PDFs after compression because images, forms, signatures, and annotations may be affected by real compression engines.
Large or image-heavy PDFs can be slow or exceed browser memory limits.

Method Explanation

  1. 1. Upload or select a PDF file.
  2. 2. Validate the file type and size.
  3. 3. Choose a compression level.
  4. 4. Optimize supported PDF content such as images, metadata, and unused data when a compression engine is connected.
  5. 5. Generate a compressed PDF.
  6. 6. Compare original and compressed file sizes.
  7. 7. Download the compressed file.

Safe Workflow and Related Tools

PDF to JPGExport pages as images when a workflow needs previews.JPG to PDFRebuild a simple PDF from optimized JPG pages.Image CompressorShrink large source images before making a PDF.PDF ToolsFind merge, split, unlock, and page-number tools.

Frequently Asked Questions

A PDF compressor reduces PDF file size by optimizing supported document data such as images, metadata, object streams, and unused content.

Related tools

More tools to try

Merge PDF
PDF Splitter
Rotate PDF
PDF Page Number Adder
PDF Metadata Viewer

Related reading

Learn the formula, assumptions, examples, or context behind this tool.

How PDF compression worksUnderstand what shrinks a PDF and where file size comes from.