PDF Compressor Online
Reduce PDF file size using simple quality presets and optional advanced controls. Balance document clarity and size reduction directly in your browser. All processing happens locally in your browser.
Choose a PDF to Compress
Drop one PDF here or choose a file from your device.
PDF document · One file at a timePrivacy Notice: Compression runs directly in your browser. PDF documents are never uploaded to any server.
What is a PDF compressor and how does it work?
A PDF compressor online reduces the file size of your PDF documents so you can email them, upload them to websites, and save device storage. It optimizes high-resolution scanned pages, re-encodes images with efficient compression, and cleans out duplicate fonts and background metadata.
Why are some PDF files so large in the first place? It usually comes down to how they were created:
Scanned Documents
Office scanners capture paper pages as full-color raw photos at 300 DPI or higher. A 10-page document can easily weigh 20 MB to 40 MB.
Embedded High-Res Photos
Presentations and brochures exported with camera-quality images carry megabytes of pixel data that no normal computer screen can display.
Text-Heavy Digital PDFs
Documents exported straight from Microsoft Word or Google Docs use crisp vector fonts. They are often already under 500 KB and need little to no compression.
Local Browser Processing
This tool runs entirely on your device. Your sensitive paperwork is never uploaded to remote servers or stored in any cloud database.
Need to meet an exact upload limit for an exam or portal?
If you are applying for a job, college admission, or government scheme that requires files under a strict ceiling like 100 KB, 200 KB, 500 KB, 1 MB, or 2 MB, use our dedicated Compress PDF to Exact Size tool. It automatically tests settings to make sure your file fits under the portal limit without guesswork.
How to compress a PDF online
You can shrink your PDF file size in four easy steps without installing any software:
Choose your PDF file
Drag and drop your PDF into the upload box above, or click to browse files from your computer or phone.
Select a compression preset
Pick Balanced for everyday office paperwork, Light for contracts with tiny footnotes, or Strong when you need maximum size reduction. You can also open Custom settings to set exact DPI and quality values.
Click Compress PDF
Your browser processes each page in memory, optimizing images and rebuilding the PDF. Nothing is sent across the internet.
Check the result and download
Compare the new file size and percentage saved against the original file, preview the pages, and click Download.
Helpful Tip: Keep Your Original File
When you apply strong compression, pages are rebuilt as optimized images. Text remains clear to read and print, but you may no longer be able to select or copy individual text characters. Always save your original document as a backup.
Choosing the right preset: Light, Balanced, or Strong
Every compression task is a balance between visual sharpness and smaller file size. Here is how each setting works in practice:
| Preset | Resolution & Quality | Best Used For | Typical File Size Drop |
|---|---|---|---|
| Light | 200 DPI, 85% JPEG Quality | Contracts, blueprints, schematics, fine diagrams, and certificates where tiny text and signatures must stay razor-sharp. | 25% to 50% reduction on scanned documents. Near-original visual quality. |
| Balanced | 150 DPI, 70% JPEG Quality | Invoices, office reports, presentations, coursework, bills, and everyday business files. Recommended default. | 50% to 75% reduction on heavy scans. Looks great on all phone and computer screens. |
| Strong | 96 DPI, 50% JPEG Quality | Archiving old paper records, sending large multi-page attachments over slow internet connections. | 70% to 90% reduction. Maximum byte savings while keeping text clearly readable. |
| Custom | 72–300 DPI, 30–95% Quality | Specific printing guidelines, publication limits, or fine-tuning grayscale conversion. | Customized to your exact preferences. |
Examples of how different PDF documents compress
Different types of PDF files respond differently to compression. Here are real benchmark examples showing what happens to various common documents:
| Document Type | Original Size | Preset Applied | Compressed Size | Savings | Practical Takeaway |
|---|---|---|---|---|---|
| Scanned Office Invoices (8 Pages) | 16.4 MB | Balanced (150 DPI) | 2.3 MB | 86% smaller | Scanners save uncompressed raw bitmaps. Balanced compression cleans out excess pixels without losing stamp or signature clarity. |
| Color Product Catalog (6 Pages) | 24.5 MB | Strong (96 DPI) | 1.8 MB | 92% smaller | Contains heavy camera photographs. Strong compression downsizes images to screen resolution, making it email-friendly. |
| Legal Employment Agreement (4 Pages) | 6.8 MB | Light (200 DPI) | 2.9 MB | 57% smaller | Light compression preserves small 8pt legal clauses and handwritten pen strokes while cutting file size in half. |
| Word Exported Research Paper (15 Pages) | 420 KB | Any Setting | 410 KB | ~2% smaller | Files created directly in text editors contain clean vector fonts. They are already tiny and do not need image rasterization. |
Notice the difference: scanned paper and photo-heavy brochures can shrink by 80% to 90%. But if your PDF is already an exported Word document under 500 KB, you do not need to compress it further.
Common use cases for compressing PDF files
Here are the most common situations where people use this tool to shrink PDF size:
What happens to your document during compression?
Before compressing your files, here are a few technical trade-offs to keep in mind:
Text Selectability
When you compress a PDF using image downsampling, pages are converted into clear visual images. Text looks identical on screen and in print, but you may not be able to highlight words with a cursor.
Interactive Forms & Bookmarks
Fillable text fields, drop-down menus, and table-of-contents bookmarks are flattened during image rebuilding. If you need fillable forms, keep the original.
Digital Signatures
Any tool that changes the internal structure of a PDF breaks pre-existing digital cryptographic signatures. If you have a signed contract, keep the original version intact.
Metadata Removal
If you check the Remove Metadata option, hidden details like author names, software versions, and edit history are stripped out to protect your privacy.
Privacy and secure browser-local processing
Most online PDF tools upload your sensitive documents to their cloud servers to do the processing. That means your bank statements, medical records, tax documents, and personal contracts end up stored on remote computers.
TryFormatter works completely differently. Our PDF compressor runs 100% inside your web browser using modern WebAssembly and JavaScript. Your files never leave your computer or phone, no data is sent across the internet, and nothing is saved on our servers. As soon as you close your browser tab, your document is gone from memory.
Frequently Asked Questions
How does this PDF compressor reduce file size?
The tool renders each page, applies your chosen resolution (DPI) and image quality settings, removes unnecessary metadata streams, and rebuilds a smaller PDF file entirely inside your browser.
What is the difference between Light, Balanced, and Strong presets?
Light (200 DPI, 85% quality) keeps near-original sharpness for fine text. Balanced (150 DPI, 70% quality) is our recommended default for everyday office files. Strong (96 DPI, 50% quality) gives maximum size reduction for email and archiving.
Can I compress a scanned PDF without losing quality?
Yes. Use the Balanced or Light preset. Scanned pages are usually saved at unnecessarily high resolutions (300 DPI+). Reducing them to 150 DPI cuts 50% to 75% of the file size while keeping letters, stamps, and signatures completely legible.
Why did my PDF size increase or stay the same after compression?
This happens when a PDF was exported directly from Word or Google Docs and only contains vector text. Vector text is already tiny (often under 400 KB). Converting vector text into image pages takes more data than the original instructions. If your file is already tiny, you don't need to compress it.
How can I reduce a PDF to an exact size like 100 KB, 200 KB, or 1 MB?
If you need to meet an upload limit for an exam or government portal, use our dedicated Compress PDF to Exact Size tool. It tests compression levels and reports whether the target was reached; some files cannot fit without further changes.
Can I compress password-protected PDF files?
If the PDF is encrypted with an open password, you must enter the password to unlock it before compressing. The tool will let you know if a file is password-protected.
Are my documents uploaded to any server?
No. All PDF processing happens locally on your device in your web browser. Your files, documents, and personal data never leave your computer or phone.
