How to Compress a PDF to 100KB (Free, Browser-Based, 2026)
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Quick Answer
To compress a PDF to 100KB: upload to FileCurve PDF Compressor, choose "Maximum" compression, which downsamples images to 72dpi and converts embedded JPEGs to quality 50. A typical 2–5MB scanned PDF reaches 80–150KB. For text-only PDFs, 100KB is usually already achievable.
Step-by-step
- 1
Upload your PDF to FileCurve PDF Compressor.
- 2
Choose "Maximum" compression level (image downsample + re-encode).
- 3
Verify the output size.
- 4
If still above 100KB and the PDF has color photos, convert to grayscale — halves size again.
- 5
For multi-page scans, re-scan at 150dpi next time (not 600dpi).
- 6
Download.
Expected output
Format
PDF, images downsampled to 72dpi
Quality setting
Maximum compression (lowest quality)
Estimated size
5–10% of a typical scanned PDF
Why you might need this
- →Indian government portals (PAN, EPFO, UIDAI) capping PDFs at 100KB
- →College admission PDF uploads
- →Exam form document uploads
- →Email attachments where multiple PDFs need to fit under a cap
Troubleshooting
PDF is still 500KB after max compression
Scanned at high DPI. Use "Convert to image" workflow, or regenerate the PDF from a re-scan at 150dpi.
Text is blurry after compression
Downsampling hurt OCR'd text. Use grayscale + 150dpi minimum for text-heavy docs.
Frequently asked questions
Why is my PDF so large?
99% of oversized PDFs are scans. A 600dpi scan of one A4 page can be 5–10MB. Re-scan at 150dpi or compress hard.
Will compression make my PDF unreadable?
Text stays readable down to 100KB. Photo quality suffers — acceptable for form uploads, not for print.
Is 100KB enough for a 10-page PDF?
For text-only PDFs, yes. For scans, compress to grayscale and accept some quality loss.