How to Compress a PDF Under 100KB (Free, No Upload)

4 min readUpdated July 22, 2026

Government portals, job applications and email attachments often enforce hard size limits — 100KB, 200KB or 1MB. A scanned or image-heavy PDF blows past those instantly. Here's how to get a PDF under 100KB for free, without uploading it to anyone's server.

Why PDFs get so big

Most oversized PDFs are large because of images — scans, photos and screenshots stored at full resolution. Compression re-encodes those images at a smaller size and quality, which is where the savings come from. Text-only PDFs are already small; image-based ones shrink the most.

Compress a PDF under 100KB in 3 steps

  1. 1Open the Compress PDF tool and drop your PDF in. It's processed on your device — nothing is uploaded.
  2. 2Pick a compression level. Start with a higher strength (lower quality) and check the resulting size shown after processing.
  3. 3If it's still over your limit, increase the compression a little more and re-run, then download the smaller PDF.

Tips to hit a strict limit

If a single strong pass isn't enough, split the document and keep only the pages you need, or convert colour scans to grayscale before compressing. For text documents that must stay razor-sharp, aim for the smallest size that keeps text legible rather than the absolute minimum.

Private by design

Because compression runs entirely in your browser, your document — a contract, an ID scan, a bank statement — never leaves your device. Nothing is stored once you close the tab.