Quick Answer
Upload your PDF, select "Target size," enter 100KB, and click "Compress." Images are heavily downscaled to reach the target. Best for text-heavy documents.
What You'll Need
Step-by-Step Guide
Follow these 5 simple steps to get the job done in about 30 seconds - 1 minute. Check off each step as you go.
Open the Compress Tool
Navigate to the PDFly Compress PDF tool. You'll see a clean upload zone ready for your file.
Upload Your PDF
Drag and drop your PDF into the upload zone, or click to browse. The file loads immediately and shows current file size.
Choose Compression Level
Select from Basic (light compression, best quality), Strong (balanced), or Extreme (maximum size reduction). For target-specific compression, enter a custom file size target like 1MB or 100KB.
Compress and Compare
Click "Compress." The tool processes your file and shows the before/after file sizes. You can see exactly how much space you saved.
Download the Optimized PDF
Click "Download" to save your compressed PDF. The optimized file maintains text clarity while reducing image sizes and removing redundant data.
Key Takeaways
Choose between Basic, Strong, Extreme, or custom target size
Lossless mode removes metadata without affecting quality
Typical compression saves 30-70% of the original file size
Always verify text readability after Extreme compression
Pro Tips & Best Practices
For text-heavy PDFs, Basic compression is usually sufficient — you'll save 20-40% with no visible quality loss.
Image-heavy PDFs benefit most from Strong or Extreme compression, which downsamples images intelligently.
Use the "Target size" option when you need to meet a specific file size requirement (e.g., for email or upload limits).
Lossless compression removes only metadata and unused objects — use it when every pixel matters.
Common Mistakes to Avoid
Using Extreme compression on text-only PDFs
Text-heavy PDFs barely shrink with Extreme mode. Use Basic or Strong instead — the quality loss isn't worth it.
Not checking the compressed file before sharing
Always open the compressed PDF to verify text readability and image quality before sending.
Compressing an already-compressed PDF
Already small PDFs won't shrink much further. Focus compression on large files (5MB+) for best results.
Ready to Try It Yourself?
That's it! You now know how to compress a pdf to 100kb using PDFly. The entire process takes less than a minute and runs entirely in your browser — your files are never uploaded to a server. Ready to try it yourself? Use the Compress PDF tool below to get started right now.
Open Compress PDF — Free, No SignupFrequently Asked Questions
It depends on the compression level. Basic compression has minimal quality impact. Strong and Extreme modes reduce image quality more aggressively. Use Lossless mode if quality is critical.
Typical compression reduces file size by 30-70%. Text-heavy PDFs compress less, while image-heavy PDFs can compress up to 90% with Extreme mode.
No. Since processing is done in your browser, the only limit is your device's memory. Files up to 2GB have been tested successfully.