PDFAirlock

Compress PDF

Shrink scanned PDFs dramatically — everything stays on your device.

Processed on your device — nothing is uploaded. Works offline.

Don't trust us — test us

Load this page, then turn off your wifi. The tool keeps working, because your file is processed by your own browser — there is no server involved and nowhere to upload to. How to verify this yourself →

Frequently asked questions

How much smaller will my PDF get?

Scanned documents typically shrink 5–15×. The compressor re-renders pages as optimized images, so results depend on content and the level you pick. The before/after size is shown before you download.

Will text still be selectable after compression?

In Strong/Balanced/Light mode, pages are re-rendered as images, so text is no longer selectable — like a good scan. For digitally-created PDFs where you need selectable text, use Lossless mode (smaller gains, structure-level cleanup only). We tell you this before you run it because most tools don't.

Are my files uploaded to a server?

No. All processing happens inside your browser using WebAssembly and JavaScript. Our server only serves the app itself — there is no endpoint that can receive files. You can verify this in your browser's network tab, or turn off your wifi after the page loads: everything still works.

Is there a file size limit?

No hard limit — your device's memory is the ceiling. Files up to a few hundred MB work well on a typical laptop. Very large files may be slow or fail on low-memory devices; nothing is ever truncated silently.

Do I need to create an account?

No. No account, no email, no cookies. The free tools are simply free.

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