When you need a PDF under 100 KB
Compressing a PDF to 100 KB is usually not a choice. It's what a strict upload box demands. Some government forms, exam registrations and ID verification pages accept only very small files, and they reject anything over the limit without explanation.
The files people most often need to fit are single-page scans: an ID card, a passport photo page, a proof of address, a signed declaration or a certificate. These are exactly the documents where 100 KB is realistic, because a single scanned page is mostly one photo, and photos are what our engine recompresses.
The trade-off at 100 KB
100 KB is a tight target. To get there, ConvertirDocs reduces the resolution and JPEG quality of the photos in the PDF, one step at a time, and stops as soon as the file is under the limit. That means you get the best quality that still fits, not the lowest possible.
Still, expect a visible difference on scans: fine print may look softer, and colors may flatten. Before you submit, open the downloaded file and zoom in on the parts that matter, like your name, ID number and signature. If they're readable, you're done. Text that was typed into the PDF (not scanned) is never recompressed, so it stays sharp at any target.
If it can't reach 100 KB
Sometimes the file simply can't get that small. A multi-page scan, or a PDF whose weight comes from fonts, transparent images or CMYK graphics, may stay above 100 KB even at the lowest quality step. In that case ConvertirDocs doesn't fail silently: it hands you the smallest file it achieved and tells you why it stopped there.
A few things usually help. Keep only the page the portal really needs with “Extract pages” or “Remove pages”, then compress again. If you're starting from a phone photo, “Scan to PDF” with the black and white document filter produces lighter pages than a full-color photo. And check the portal's instructions: if it accepts several uploads, one small file per page may work better than one big file.
Private by design
The documents that need to fit under 100 KB are often the most sensitive ones you own. With ConvertirDocs they are processed in your browser and never leave your device. Nothing is uploaded or stored, and you don't need an account or an email address to use it.