Compress PDF to 100KB Online
Drop your PDF — it targets 100KB automatically, ready for upload.
100% in your browser — files never uploaded
Why 100KB is a common portal ceiling
Government forms, exam applications and email gateways often cap PDF attachments at 100KB. This page opens directly in Target file size mode with 100KB pre-selected, so you skip picking a preset manually.
How the 100KB target is reached
Each page is re-rendered on your device and re-encoded as an optimized JPEG, then rebuilt into a new PDF — running up to four passes automatically to land at or under 100KB.
If 100KB isn't reachable
For very long or image-heavy documents, 100KB may be mathematically unreachable — the tool then returns the smallest file the document allows, with a clear note saying so.
Compress a PDF to 100KB in One Step
This tool is Compress PDF pre-set to a 100KB target, so there's no preset to pick — drop your file and it runs the same multi-pass compression engine used across CoreTools, searching for the highest quality that still lands under 100KB. Rendering and rebuilding happen entirely in your browser.
When 100KB Is the Number a Portal Demands
A 100KB ceiling is common on government and recruitment portals, where a file even a kilobyte over gets rejected. Starting already locked to 100KB removes the guess-and-retry cycle of picking a compression level and checking the result size manually.
Other Targets and Presets
If your portal names a different KB limit, the full Compress PDF tool exposes every target size plus the Best Quality, Recommended and Smallest File presets on the same underlying engine.
Frequently asked questions
How do I compress a PDF to exactly 100KB?
Drop your PDF here — Target file size mode is already set to 100KB, so the tool automatically searches for the highest quality that fits under that limit.
Is my PDF uploaded anywhere?
No. Every page is rendered, re-encoded and rebuilt entirely in your browser — the file is never transmitted to a server.
Will the text still be selectable after compression?
No. Pages are re-rendered as optimized images, so the output is a visual copy without selectable text.
What if my PDF can't reach 100KB?
If the target is mathematically unreachable for your page count, you still get the smallest file the document allows, with an honest note explaining why.
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OpenData verified: 2026-07-17 · All processing happens in your browser — no files are ever uploaded.