Mac users have two built-in options for compressing PDFs without any additional software: macOS Preview and the browser.
Reduce PDF file size by up to 70% without losing quality, right in your browser. Need to edit the content first? Try our PDF to Word converter or PDF merger.
Upload your PDF file and compress it to reduce file size
PDF compression is the process of reducing the file size of a PDF (Portable Document Format) document without significantly compromising its visual quality or functionality. PDF compression works by optimizing images, removing unnecessary metadata, compressing text and graphics, and restructuring the PDF's internal structure. According to MDN Web Docs, PDFs can contain various types of content including text, images, vector graphics, fonts, and metadata, all of which can be optimized for smaller file sizes.
Compressing PDF files is essential for several reasons: reducing file size for email attachments (many email services have size limits), speeding up web uploads and downloads, saving storage space, improving document sharing efficiency, and ensuring compatibility with systems that have file size restrictions. PDF compression is particularly important for PDFs containing high-resolution images, scanned documents, or documents with embedded fonts and graphics.
Our PDF compressor uses advanced compression algorithms to optimize your PDF files entirely in your browser. This client-side processing ensures your PDF files remain completely private and secure. All compression happens locally, so your documents never leave your device or get uploaded to any server.
Large PDF files can be difficult to share via email, slow to upload, and consume significant storage space. High-resolution images and embedded fonts increase file size substantially.
document.pdf (8.5 MB)
Too large for email
Compressed PDFs are smaller, faster to share, easier to upload, and consume less storage. Images are optimized, metadata is removed, and the file structure is streamlined.
document.pdf (2.1 MB)
75% smaller, email-ready
Real data showing the benefits of compressing PDF files
According to MDN Web Docs, PDF files can contain uncompressed content that significantly increases file size. Client-side PDF compression enables users to optimize their documents for sharing and storage without compromising privacy or security.
Compressing PDF files offers numerous benefits for sharing, storage, and efficiency. Here are the key advantages of using our PDF compressor:
Many email services have file size limits (typically 10-25MB). Compressing PDFs allows you to send documents via email without exceeding these limits. Smaller files also upload and download faster, improving communication efficiency.
Compressed PDFs upload faster to cloud storage, content management systems, and web forms. This saves time and reduces bandwidth usage, especially important for users with slower internet connections or mobile data plans.
Compressed PDFs consume less storage space on your device, cloud storage, or servers. This is especially valuable when managing large document libraries, archives, or when storage space is limited or costly.
All PDF compression happens entirely in your browser using client-side JavaScript. Your PDF files never leave your device, aren't uploaded to any server, and aren't stored anywhere. This ensures complete privacy and security for sensitive documents.
Client-side processing means instant compression without waiting for file uploads or server processing. Compress PDF files in seconds, even for large documents. No internet connection required after the initial page load.
Choose from three compression levels (low, medium, high) to balance file size and quality. Low compression maintains high quality, while high compression maximizes file size reduction. Select the level that best fits your needs.
Companies like Adobe and iLovePDF offer PDF compression services, but they require file uploads to their servers. Our client-side approach ensures your documents remain completely private, making it ideal for sensitive business documents, legal files, medical records, and confidential materials.
Our PDF compressor uses advanced compression algorithms to optimize your PDF files directly in your browser. Here's how the compression process works:
Upload your PDF file. The tool analyzes the PDF structure, identifies images, fonts, and other content that can be optimized.
Based on your selected compression level, the tool optimizes images, removes unnecessary metadata, compresses text and graphics, and restructures the PDF for maximum efficiency.
Once compression is complete, preview the file size reduction and download your optimized PDF. The compressed file maintains visual quality while being significantly smaller.
To get the best results when compressing PDF files, follow these best practices:
PDF compression serves a wide variety of professional and personal needs. Understanding these use cases can help you determine when compression is the right solution:
Many email services limit attachment sizes to 10-25MB. Compressing PDFs allows you to send documents via email without exceeding these limits. This is essential for sharing reports, invoices, contracts, and other business documents.
Compressed PDFs also upload and download faster, improving communication efficiency and reducing bandwidth usage. This is particularly valuable for users with slower internet connections or mobile data plans.
Many web forms, job applications, and document submission systems have file size limits. Compressing PDFs ensures your documents meet these requirements and upload quickly. This is essential for online applications, document submissions, and content management systems.
Faster uploads also improve user experience, especially on mobile devices or slower connections. Compressed PDFs reduce waiting time and improve the likelihood of successful uploads.
Compressed PDFs consume less storage space on your device, cloud storage, or servers. This is valuable when managing large document libraries, archives, or when storage space is limited or costly. Organizations can save significant storage costs by compressing their PDF archives.
For individuals, compressed PDFs allow you to store more documents on your device or cloud storage without upgrading your storage plan. This is especially useful for mobile devices with limited storage capacity.
Mobile devices often have limited storage and data plans. Compressing PDFs before sharing via messaging apps, social media, or cloud services reduces data usage and storage consumption. This makes it easier to share documents on mobile platforms.
Compressed PDFs also load faster on mobile devices, improving the user experience when viewing documents on smartphones or tablets. This is essential for mobile-first workflows and remote work scenarios.
When archiving documents for long-term storage, compressing PDFs reduces storage requirements while maintaining readability. This is valuable for legal documents, medical records, financial statements, and historical archives where space efficiency matters.
Compressed archives are also faster to backup and restore, reducing backup time and storage costs. This is essential for organizations managing large document repositories.
PDFs containing many high-resolution images, scanned documents, or photographs can be very large. Compression optimizes these images while maintaining visual quality, making the documents more manageable and shareable.
This is particularly useful for portfolios, catalogs, presentations with many images, and scanned document collections. Compression can reduce file size by 50-70% while maintaining acceptable visual quality.
Upload your PDF file using the upload button or drag and drop it into the designated area. Select your desired compression level (low, medium, or high), then click Compress PDF. The tool will optimize your PDF by compressing images, removing unnecessary metadata, and optimizing the file structure. Once compression is complete, download your compressed PDF file.
Yes, our PDF compressor is 100% free to use. There's no registration required, no account needed, and no hidden fees. All PDF compression happens in your browser, so your files never leave your device and remain completely private.
Our PDF compressor offers three compression levels: Low compression maintains high quality with moderate file size reduction (10-30%), ideal for documents where quality is important. Medium compression provides a good balance between file size and quality (30-50% reduction), suitable for most use cases. High compression maximizes file size reduction (50-70% reduction) with some quality loss, perfect for web uploads and email attachments.
PDF compression can reduce quality depending on the compression level chosen. Low compression maintains near-original quality. Medium compression may slightly reduce image quality but remains suitable for most purposes. High compression may result in noticeable quality reduction, especially for images. Text and vector graphics are typically unaffected. Choose the compression level based on your quality requirements.
Absolutely. All PDF compression happens entirely in your browser using client-side JavaScript. Your PDF files never leave your device, aren't sent to any server, and aren't stored anywhere. This ensures complete privacy and security for sensitive documents, business files, and personal information.
Our PDF compressor can handle PDFs up to several megabytes in size. For optimal performance, we recommend files under 10MB. Very large PDFs with many high-resolution images may take longer to process, but all compression happens in your browser without any file size limits.
Currently, our tool supports standard PDF files. Password-protected or encrypted PDFs require the password to be entered first before compression. We're working on adding enhanced support for password-protected PDFs in a future update.
PDF compression specifically focuses on reducing file size through image compression and data optimization. PDF optimization is a broader term that includes compression but may also involve removing unnecessary elements, optimizing fonts, and restructuring the PDF for better performance. Our tool performs both compression and optimization to achieve the best results.
Guides for compressing PDFs in specific situations:
Paste one iframe and the FixTools SDK automatically keeps its height in sync.
Explore other PDF tools to work with your documents:
Convert PDF pages to images
Combine multiple PDFs
Split PDF into separate files
Convert to PNG with transparency
Convert to editable Word format
Turn any PDF into a multiple choice quiz powered by AI.
View all PDF tools
Not all PDF compressors are equal. The main differences come down to where your file is processed, how much control you have over quality, and what the tool costs. Here is how the most common options compare.
| Feature | FixTools Compressor | Adobe Acrobat | macOS Preview | Print to PDF |
|---|---|---|---|---|
| Cost | Free | ~$15+/month | Free (macOS only) | Free |
| File processed on server | ❌ Browser-only | ✅ Cloud upload | ❌ Local | ❌ Local |
| Compression levels | 3 (low / med / high) | Fine-grained slider | Presets only | Fixed (low quality) |
| Preserves hyperlinks | ✅ | ✅ | Sometimes | ❌ |
| Preserves form fields | ✅ | ✅ | Sometimes | ❌ |
| Works on Windows | ✅ | ✅ | ❌ | ✅ |
| Requires install | ❌ None | ✅ Required | Built-in macOS | Built-in |
| Best for | Quick, private compression anywhere | Professional PDF workflows | Mac users, light compression | Last resort — strips metadata |
The “Print to PDF” workaround is worth calling out specifically: it is often suggested online as a quick compression trick, but it re-renders your PDF through the OS print system, which strips interactive elements, removes hyperlinks, flattens form fields, and can significantly degrade text sharpness. Use it only as a last resort when no other option is available.
From the FixTools Blog
How to Compress a PDF Without Losing Quality
Why PDFs get large, what compression actually does, and how to match quality settings to your use case.
Runs locally in your browser
No server upload during processing
No server-side file retention
No watermark added
Drop the PDF Compressor into a blog post, product docs, intranet, or school portal with one iframe. Processing, privacy, and usage limits are the same as on the full tool page.
Embed code
<iframe
src="https://www.fixtools.io/pdf/pdf-compressor?embed=1"
width="100%"
height="780"
frameborder="0"
style="border:0;border-radius:16px;max-width:900px;"
title="PDF Compressor by FixTools"
loading="lazy"
allow="clipboard-write"
></iframe>Attribution-friendly: a small "Powered by FixTools" link appears in the embed footer.
macOS Preview has offered a Reduce File Size option via File > Export as PDF > Quartz Filters since Mac OS X Tiger. The filter works by applying a Quartz filter that re-encodes all embedded content at lower quality. The problem many Mac users discover is that Preview's Reduce File Size filter is not well calibrated. It applies a fixed quality setting that can produce very poor results for already-optimised PDFs, sometimes making text slightly blurry at the edges, while producing inconsistent results on different document types. Additionally, the filter does not expose quality settings, so you get one fixed compression level with no way to choose between aggressive and gentle compression. For some PDFs, particularly those already at medium resolution, Preview's filter makes the file slightly larger rather than smaller, which is a well-documented macOS quirk that has persisted across multiple versions of the operating system.
Browser-based compression with FixTools running in Safari or Chrome on Mac offers several advantages over Preview. First, FixTools provides three compression levels of low, medium and high, giving control over the quality-to-size trade-off that Preview does not offer. Second, FixTools uses a more modern compression pipeline that handles JPEG re-encoding more cleanly than the legacy Quartz filter, which was designed for print workflows rather than digital distribution. Third, FixTools strips metadata and unused font data alongside image compression, which Preview does not do, producing a cleaner output file. On a modern M-series MacBook, FixTools compresses a 10MB PDF in 5 to 10 seconds in Safari, which is comparable to Preview's processing time. On an Intel MacBook the same operation typically takes 10 to 15 seconds, still well within an acceptable range for everyday tasks.
For Mac users who need to automate compression of many PDFs, Automator built into macOS offers a PDF action pipeline that can be combined with third-party utilities. For occasional compression, FixTools in a browser tab is faster to access than setting up an Automator workflow. For power users who compress dozens of PDFs daily, the command-line tool Ghostscript, installable via Homebrew, offers the most control and batch processing capability. But for most Mac users who compress one or two PDFs per week, FixTools in Safari eliminates the need to install anything and provides better results than Preview. The choice ultimately depends on volume: occasional users benefit from the browser, while power users with hundreds of PDFs per month should invest the time to set up a Ghostscript script that processes entire folders automatically.
It is also worth noting how each option interacts with privacy. Preview runs natively and never touches the network, so files stay entirely on the machine, which is reassuring for confidential documents. FixTools is browser-based but processes locally as well, so no file leaves your Mac during compression. You can confirm this by opening Safari's Web Inspector or Chrome's DevTools, switching to the Network tab, and watching for any outbound file transfer during the compression step. There is none. This puts FixTools on equal privacy footing with Preview while offering meaningfully better compression results, more control, and an interface that scales gracefully across compression levels.
Open Safari or Chrome on your Mac and go to fixtools.io/pdf/pdf-compressor. Upload your PDF from Finder, choose medium compression, and download the result. Compare the output size with Preview's Reduce File Size to see the difference.
Step-by-step guide to compress pdf on mac:
Open the compressor in your browser
Open Safari or Chrome on your Mac and navigate to fixtools.io/pdf/pdf-compressor. The page loads in under a second on a typical broadband connection and shows the upload area front and centre with no account prompts.
Upload your PDF
Drag the PDF directly from a Finder window onto the upload zone, or click to open the standard macOS file picker and navigate to your document in Documents, Desktop, iCloud Drive, or any connected volume.
Choose compression level
Select medium for most documents because it produces a strong balance of size reduction and visual quality. For maximum reduction, choose high; for important photographs where every pixel matters, choose low.
Compress the file
Click the Compress PDF button. On an M-series Mac, a typical 10MB file processes in under 10 seconds, and a 30MB scanned PDF processes in approximately 20 to 30 seconds depending on page count and content density.
Download to Finder
Save the compressed PDF to your Downloads folder or drag it from the browser straight into a Finder window. The file is ready to email through Mail, upload to iCloud, share via Messages, or attach in Microsoft Outlook for Mac.
Common situations where this approach makes a real difference:
A graphic designer on a MacBook Pro needs to email a 25MB portfolio PDF to a potential client. She tries Preview's Reduce File Size, which produces a 22MB output. The reduction is almost nothing and the file still bounces off her client's corporate mail server. She switches to FixTools in Safari and uses medium compression, reducing the portfolio to 7.8MB. Image quality on the cover photographs remains crisp at the recipient's standard zoom level, and the email lands cleanly without provoking the inbound size filter that had previously blocked her work.
A university lecturer on a Mac compresses lecture slides before uploading to the virtual learning environment. PowerPoint-exported PDFs average 18MB per lecture due to high-resolution photographs of historical artefacts. Preview compresses them to 14 to 16MB, which still exceeds the VLE's 10MB upload limit. FixTools medium compression brings each lecture deck to 4 to 6MB, comfortably under the cap. Slide images remain clear when students view them on laptop screens, and the lecturer can publish a full term of recorded lectures without exceeding the platform's storage allocation.
A solicitor on an iMac compresses client document bundles before secure portal upload. He previously used Adobe Acrobat for compression at almost $240 per year. After discovering FixTools, he compresses 12 to 15MB document bundles to 3 to 4MB in Safari without any software cost, matching the Acrobat output quality at high compression. Over the course of a year he saves the full Acrobat subscription, redirecting the budget toward practice management software. His paralegals adopt the same workflow on their MacBook Airs.
A Mac-using HR manager needs to archive a year of candidate CVs. Each CV averages 4MB, and 200 CVs would occupy 800MB on the company shared drive. Medium compression via FixTools reduces the average CV size to 1.1MB. The 200 compressed CVs take 220MB, fitting comfortably on a standard USB drive for offsite backup and loading several times faster in the company HR document viewer. Search and preview functions inside the HR system become noticeably more responsive once the archive is rebuilt at the smaller size.
Get better results with these expert suggestions:
Drag and drop from Finder for faster upload
On Mac, you can drag a PDF directly from a Finder window onto the FixTools upload area in your browser. This is faster than clicking Choose File and navigating through the Open dialog, especially if your Finder is already showing the right folder. You can also drag the compressed file from the browser Downloads bar back to a Finder window to place it directly in a specific project folder, which is useful for keeping client work tidy and avoiding clutter in the default Downloads location.
Compare Preview vs FixTools on your specific file
Try both Preview's Reduce File Size and FixTools medium compression on the same PDF and compare the resulting file sizes and quality. For some document types one approach outperforms the other. Generally, FixTools produces better results for scanned PDFs and image-heavy files while Preview's output for already-compact text PDFs is comparable. Doing this test on a single representative file builds confidence that you are using the right tool for the kind of documents you handle most frequently.
Use Ghostscript via Homebrew for batch compression
If you regularly compress dozens of PDFs per month on a Mac, install Homebrew and then Ghostscript. The command gs -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -sOutputFile=output.pdf input.pdf compresses a PDF equivalent to FixTools medium compression. This can be scripted to process entire folders automatically, freeing you from the manual sequential workflow that browser tools require for batches above thirty files.
Check the output in Preview before sharing
After compressing in FixTools, open the result in macOS Preview to review quality at 150 percent zoom. Preview renders PDFs using the same engine as most macOS PDF viewers, so what you see in Preview is representative of what recipients on Mac will see in Mail, Notes, and other Apple apps. If quality is insufficient on key pages such as a cover photograph or a detailed diagram, recompress the original at a lower setting rather than living with results that disappoint the recipient.
More use-case guides for the same tool:
Other tools you might find useful:
PDF Merger
Merge PDF files before or after compressing.
PDF Splitter
Split large PDFs before compressing each part.
Image Compressor
Compress images before embedding in PDF.
Compress PDF on Windows
Compress a PDF on Windows 10 or Windows 11 for free. Use FixTools in Chrome or Edge, no software to install. Compare with Adobe and iLovePDF for Windows.
Compress PDF Without Losing Quality
Compress a PDF without losing visible quality. Free browser tool with adjustable compression levels. Understand what quality loss means technically and how to minimise it.
Compress PDF in Your Browser, No Upload Required
Compress PDF directly in your browser without uploading to any server. FixTools uses the FileReader and Canvas APIs so your file never leaves your device.
Compress PDF Online Free
Compress PDF online for free with no file upload. All processing happens in your browser. No sign-up, no watermark, no cloud. Compare with iLovePDF and Smallpdf.
Compress Scanned PDF Files
Reduce scanned PDF file size fast. Scanned PDFs are large because each page is a raster image at 300 DPI. FixTools resamples those images to cut size by 70-80%.
Compress PDF on iPhone
Compress a PDF on iPhone without downloading any app. Use FixTools in Safari to reduce PDF size directly on your iPhone, works with Files app and Share Sheet.
Open PDF Compressor to review its free limits and processing method.
Open PDF Compressor →Free tier · No account needed · Transparent limits