Free PDF Compressor
Reduce PDF file size using Ghostscript. Four quality presets from Screen to Prepress. See exact before/after size savings — no watermarks, no file size limits on basic PDFs.
Click or drag your PDF here
PDF files up to 50 MB
Balanced quality — sharing & e-readers
Lower quality = smaller file. Only affects images embedded inside the PDF.
Files are processed securely on our server and deleted immediately after compression.
About Free PDF Compressor
PDF file size is one of the most common obstacles to sharing, uploading, and storing documents. A typical PDF exported from a design tool like Adobe InDesign, a presentation saved as PDF from PowerPoint, or a scanned multi-page document with embedded photographs can easily exceed 20–50 MB — far too large for most email clients, web form upload limits, or document management portals that cap at 5–10 MB. The PDF Compressor tool uses Ghostscript, the industry-standard PDF processing engine, to analyze and optimize PDF content by resampling and recompressing embedded images at a quality level matching your intended use case. The result is a dramatically smaller PDF that opens correctly in any PDF viewer.
The compressor offers four compression presets based on the standard Ghostscript PDF output settings: Screen (72 dpi, optimized for on-screen display and email), eBook (150 dpi, balanced quality for digital distribution), Printer (300 dpi, suitable for home and office printing), and Prepress (300 dpi with high-quality color settings for professional printing). An additional Image Quality slider lets you fine-tune the JPEG compression applied to embedded images from 50% to 95%, giving expert users precise control over the quality-to-size trade-off. After compression, the tool shows the original size, compressed size, and exact bytes saved — so you can immediately evaluate whether the result meets your size requirements.
Key Features
Everything you need — no software installation required.
Ghostscript PDF Compression Engine
Powered by Ghostscript — the same engine used by commercial PDF processing software, Linux print servers, and professional publishing workflows. Ghostscript analyzes the full PDF structure, identifies embedded image data, and resamples images at the target DPI using JPEG compression. Unlike browser-based re-saving tools, Ghostscript performs deep PDF optimization that typically achieves 30–80% file size reduction on image-heavy PDFs.
Four Standard Compression Presets
Screen preset compresses to 72 DPI — optimized for on-screen viewing, email, and web display. eBook preset compresses to 150 DPI — a balanced quality level for digital distribution via email, portals, and document sharing platforms. Printer preset targets 300 DPI — suitable for home and office inkjet and laser printing where image quality matters. Prepress preset uses 300 DPI with high-quality color settings — for professional offset printing services.
Adjustable Image Quality Control
Beyond the four main presets, an Image Quality selector lets you set the JPEG compression level applied to embedded images from 50% (maximum compression, smaller file) to 95% (minimal compression, highest quality). This fine-tuning option is valuable when the default preset quality is slightly higher or lower than you need — adjust quality downward to get a smaller file or upward when image fidelity is a priority.
Before/After Size Comparison
After compression, the tool displays a three-column summary showing the original file size, compressed file size, and exact bytes saved with a percentage reduction. This immediate feedback lets you verify that the compression achieved the reduction you needed before downloading and sharing the file. If the result is not small enough, try a lower preset or reduce the image quality setting and compress again.
Text Remains Sharp at All Quality Levels
PDF text content is vector-based and is not affected by Ghostscript image compression — only embedded raster images are resampled. Text in compressed PDFs remains perfectly crisp and sharp regardless of the compression preset used. This is a key advantage over naive PDF compression methods that flatten all content to a raster image, which makes text blurry and non-searchable. Text searchability, copy-paste functionality, and document structure are all preserved.
No Watermarks — Completely Free
The compressed output PDF contains only your original content with no watermarks, service attribution, or promotional text added. This is a truly free PDF compressor — no trial mode, no premium tier required to remove a watermark. PDFs are processed over HTTPS and both the original and compressed files are permanently deleted from our servers after download. Confidential business documents and legal PDFs are handled with full privacy.
How to Use Free PDF Compressor
Get your result in seconds — completely free, no registration needed.
Upload your PDF
Click the upload area or drag and drop a PDF file onto it. Files up to 50 MB are accepted. After uploading, the filename and original file size are displayed so you can note the starting size before compression. If the PDF is password-protected, remove the password protection before uploading as password-protected PDFs cannot be processed.
Select a compression preset
Choose the compression level that matches your intended use: Screen for email and web sharing (smallest file, lowest image quality), eBook for digital document distribution (balanced), Printer for home and office printing (good quality), or Prepress for professional print production (highest quality, least compression). Use the Image Quality selector to fine-tune the JPEG compression level if needed — a lower value produces a smaller file.
Compress the PDF
Click Compress PDF to begin processing. Ghostscript analyzes the PDF structure, identifies all embedded image data, resamples images at the target DPI, and recompresses them at the selected JPEG quality level. A progress bar shows the upload and processing status in real time. Processing typically takes 5–30 seconds depending on the number of embedded images and the original file size.
Review size savings and download
When compression completes, the original size, compressed size, and exact bytes saved are displayed in three columns. Review the compression results to confirm the output file meets your size requirements. Click the download button to save the compressed PDF. If the file is still too large, compress again using the Screen preset with a lower Image Quality setting for maximum size reduction.
Compression Presets Reference
Wide format support ensures compatibility with virtually any file you upload.
| Format | Description | Best For | Quality |
|---|---|---|---|
| Screen (72 DPI) | Maximum compression. Images are resampled to 72 DPI — sufficient for reading on screen but not suitable for printing. Typically achieves 50–80% size reduction on image-heavy PDFs. | Email attachments, web form uploads, digital-only sharing | 60–80% size reduction |
| eBook (150 DPI) | Balanced compression. Images are resampled to 150 DPI — sharp enough for reading on tablet screens and laptop displays. The best general-purpose compression level for document distribution. | Document portals, digital distribution, online submissions | 40–60% size reduction |
| Printer (300 DPI) | Moderate compression. Images are resampled to 300 DPI — the standard resolution for home and office printing. PDF files are noticeably smaller than the original but retain full print quality. | Home/office printing, client reports, print submissions | 20–40% size reduction |
| Prepress (300 DPI HQ) | Light compression. Targets 300 DPI with high-fidelity color settings for professional offset printing. Achieves modest size reduction while preserving maximum print quality for commercial print production. | Professional printing, commercial print services, publishing | 10–20% size reduction |
| Image Quality 50–95 | Fine-grained JPEG quality control applied in addition to the preset. Lower values produce smaller files with more compression artifacts. Higher values preserve image quality but produce larger files. | Expert fine-tuning between preset levels | Adjustable per requirement |
Who Uses Free PDF Compressor?
Trusted by millions of users across different industries and workflows.
Email Attachments Under Size Limits
Most email services have attachment size limits of 10–25 MB. PDF reports, brochures, and presentations exported from design software can easily exceed these limits. The Screen or eBook preset reduces a typical 25 MB design PDF to 3–8 MB — well within Gmail's 25 MB limit and Microsoft 365's 20 MB limit. For internal business email systems with stricter 10 MB limits, the Screen preset provides the most aggressive compression to ensure reliable delivery.
Website and Document Portal Uploads
Government portals, legal filing systems, insurance claim forms, and university admissions platforms commonly impose PDF size limits of 2–10 MB. A scanned multi-page form with embedded images can easily exceed these limits. Compressing to the eBook or Screen preset reduces scanned document PDFs by 50–70%, ensuring they can be uploaded to any web form or portal without the frustrating 'file too large' error message.
Cloud Storage and Document Archiving
Organizations accumulating years of scanned documents and exported PDF reports can quickly consume cloud storage quotas. Batch compression of archival PDFs to eBook quality reduces storage costs and improves transfer speeds when syncing across devices. A 10,000-document archive averaging 5 MB per file (50 GB total) can be reduced to 15–20 GB at eBook quality — a 60–70% storage saving that translates directly to lower cloud storage costs.
Pre-Print Document Preparation
When preparing PDFs for professional print services, designers often work with very large source files exported at maximum quality. The Printer preset compresses embedded images to 300 DPI — which is the print resolution limit above which human vision cannot distinguish additional detail — while reducing file sizes by 20–40%. The compressed PDF prints identically to the original while being easier to upload to print service platforms and faster to process on professional print servers.
Mobile Sharing and Messaging
Sharing PDF documents via WhatsApp, Telegram, iMessage, and other messaging platforms imposes file size limits of 16–100 MB depending on the platform. Large PDFs also consume significant mobile data bandwidth when downloading on cellular connections. Compressing to Screen or eBook quality produces small, fast-loading PDFs that are comfortable to share via mobile messaging and quick to open on smartphones over LTE or 5G connections.
Digital Publishing and eBooks
Publishers, educators, and content creators distributing PDF books, course materials, and digital brochures use the eBook preset to produce files optimized specifically for screen reading on e-readers, tablets, and laptops. The 150 DPI image quality is perceptually identical to higher resolutions on screen and produces PDFs in the 2–8 MB range that download quickly from websites, load fast in browsers, and transfer quickly to e-reader devices.
Why Choose Our Tool?
Built for speed, privacy, and reliability — everything works right in your browser.
Dramatically Smaller Files with Ghostscript
Ghostscript achieves file size reductions that simple PDF re-save tools cannot match. By deeply analyzing the PDF structure and resampling individual embedded images at a target DPI rather than simply re-encoding the entire document, Ghostscript compresses only the image data that actually contributes to file size while leaving text, vector graphics, and document metadata intact. The result is genuine 40–80% size reduction on image-heavy PDFs — not the 5–15% reduction from superficial re-saving.
Four Presets Match Every Use Case
A single compression level cannot be optimal for all use cases. The Screen preset aggressively compresses for digital-only email and web use where print quality is irrelevant. The eBook preset provides the right balance for most digital document sharing. The Printer and Prepress presets preserve enough image quality for professional printing. Having four specific presets aligned with industry standards means you get the right quality-to-size ratio for your specific sharing channel without guesswork.
Text Stays Sharp and Searchable
Many free PDF compression tools work by converting the entire PDF to a rasterized image at a lower resolution — which makes text blurry, non-searchable, and unable to be selected or copied. Our Ghostscript-based compressor targets only embedded raster images for resampling. Text remains vector-based, perfectly crisp at any zoom level, fully searchable, and copy-pasteable — preserving all the functional benefits of a proper PDF document.
Transparent Size Savings Before Download
The tool shows the exact original size, compressed size, and bytes saved before you download. This transparency means you can immediately verify whether the compression achieved your target file size and decide whether to download or to try a more aggressive setting. There is no need to download, check the file size, realize it is still too large, and re-upload. The upfront size comparison saves time and makes it easy to iterate to the right compression level efficiently.
Pro Tips & Best Practices
Get the best results with these expert recommendations.
Use Screen preset for email and portal uploads
When the goal is simply to get the PDF under an email attachment or upload portal size limit and the recipient will only view the document on screen, use the Screen preset with the default 75% image quality. This combination typically reduces a 20 MB PDF to 3–6 MB — small enough for almost any email or web form upload restriction. If even more reduction is needed, lower the image quality to 65% or 50% for maximum compression.
Use eBook preset as the general-purpose choice
If you are unsure which preset to use, the eBook preset (150 DPI, 75% image quality) is the best default. It produces PDFs that look sharp on tablet and laptop screens, are small enough for most sharing needs, and maintain good enough image quality that photographs and graphics remain clearly identifiable. The eBook preset is the right choice for client deliverables, course materials, reports, and digital brochures that will be read on screen.
Do not compress PDFs that are already compressed
If a PDF has already been compressed — for example, a PDF you downloaded from a website, a PDF already processed with Ghostscript, or a PDF exported with compression by Adobe Acrobat — running it through the compressor again will produce little size reduction and may even slightly increase the file size due to re-encoding overhead. The compressor is most effective on PDFs directly exported from InDesign, PowerPoint, Word, or scanners where no compression has been applied to the embedded images.
Use Printer or Prepress preset for documents going to print
Resist the temptation to use the Screen or eBook preset for PDFs that will be physically printed — the 72–150 DPI image resolution will produce visibly blurry, pixelated images in print. For any PDF intended for an inkjet printer, laser printer, or commercial print service, use the Printer preset (300 DPI) which is the standard print resolution, or the Prepress preset for professional commercial printing. These presets still achieve meaningful size reduction while preserving full print quality.
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Frequently Asked Questions
Everything you need to know about Free PDF Compressor.