Some forms cap PDFs at 100 KB. That's not a typo. Government portals in particular often enforce it. Your scanned document is 4 MB and you have to make it 40 times smaller.
This isn't normal compression — it's surgical.
Strip every non-essential pixel
100 KB allows roughly one black-and-white scanned page at low resolution, or a few text-only pages. For anything else, you're stripping.
Delete pages that aren't required. Compress images at the highest setting. Convert colour scans to black and white if the form allows.
Use the high compression preset
Flint's compressor at High setting hits 100 KB for many small documents. The quality drops noticeably — text stays readable, photos get blocky.
If High isn't enough, the file probably needs to be rebuilt rather than compressed further. Re-scan at lower resolution, or re-export the source at 72 DPI.
Verify it's still acceptable
After getting under 100 KB, open the file and check it's still usable. Can you read every line? Is the photo recognisable?
If not, the form likely won't accept a degraded version either. Go back to the source and reduce resolution there — better quality at small size than compressed quality at small size.
FAQ
Why do forms have a 100 KB limit?
Older government systems, especially in some countries' visa or tax portals, were built when storage was scarce. The limits never got raised.
Can I fit a multi-page PDF under 100 KB?
If it's text-only and short, yes. Photos and scans almost always exceed 100 KB even compressed. Some forms accept just key pages — check what's actually required.
What's the absolute minimum a PDF can be?
A blank PDF is around 1 KB. A single short text page is 10-20 KB. Below that requires very aggressive tactics or empty content.
Is there a quality below which it's not worth submitting?
Yes — if text isn't readable or photos aren't identifiable, the form won't be accepted anyway. Don't compress past usefulness.
100 KB is tight. Drop your file into Flint's compressor on High and strip what's not needed. Sometimes you also need to go back to the source.