Need to get your PDF under 100 KB? Whether it's for an online application, government portal, or email system with strict size limits — here's exactly how to do it, free, without losing too much quality.
Why 100 KB is a common limit
Many government portals, job application systems, university admission forms, and online registration sites set a maximum upload size of 100 KB or 200 KB for uploaded documents. This is surprisingly small — a single scanned page can easily be 2–5 MB without any compression.
Getting a PDF under 100 KB requires a combination of techniques. Here is the most effective approach.
Step 1 — Compress the PDF first
Start with Bisnep PDF's free Compress PDF tool. This reduces the resolution of images inside the PDF, which is where most of the file size comes from.
Open the Compress PDF tool
Go to bisnep.com/compress-pdf-quality. No account needed.
Upload your PDF
Drop your file onto the page. Your file never leaves your browser — 100% private.
Select highest compression
Choose the maximum compression setting to get the smallest possible file.
Download and check the size
Download the file and check its size. Right-click the file → Properties (Windows) or Get Info (Mac) to see the file size.
Step 2 — Convert to greyscale if still too large
Colour information adds significant file size. If your PDF doesn't need to be in colour, convert it to greyscale using the PDF to Greyscale tool before or after compressing. This alone can reduce size by an additional 20–40%.
Step 3 — Delete unnecessary pages
Every page adds to the file size. If your PDF has blank pages, duplicate pages, or sections not required by the portal, remove them using the Delete Pages tool. Fewer pages = smaller file.
Step 4 — If still over 100 KB — split and submit only what is needed
If the portal only needs specific pages, use the Split PDF tool to extract just those pages and submit that smaller extract instead of the full document.
A text-only PDF (no images) is almost always under 100 KB already. The challenge is scanned documents and image-heavy PDFs. With maximum compression plus greyscale conversion, most single-page scanned documents can be brought under 200 KB. Getting under 100 KB may require reducing to a single page or accepting lower image quality.
| PDF Type | Typical size before | Typical size after compression |
|---|---|---|
| Single scanned page (colour) | 2–5 MB | 150–400 KB |
| Single scanned page (greyscale) | 1–3 MB | 80–200 KB |
| 5-page text report | 200–500 KB | 50–150 KB |
| Text-only 1-page document | 50–100 KB | Already under 100 KB |
All compression happens in your browser. Your PDF — even sensitive documents like ID scans or financial statements — never gets uploaded to any server.
Ready to compress?
Use Bisnep PDF's free Compress tool to start reducing your PDF size now. No sign-up, no upload, no limits.