Frequently Asked Questions about PDFBlack — Privacy & Security

Question 1

1. Are my files uploaded to any external server?

Accepted Answer

No. Absolutely no files are uploaded to internet servers. PDFBlack uses advanced JavaScript and WebAssembly libraries to process your documents locally inside your browser RAM.

Question 2

2. Is there any file size or quantity limit?

Accepted Answer

Since processing takes place on your own device, the limit depends solely on the available RAM memory of your computer or phone. You can process heavy files over 500 MB without paywalls.

Question 3

3. Does PDFBlack work without internet connection?

Accepted Answer

Yes! Once the page loads in your browser, you can disconnect from the internet and continue merging, splitting, compressing, signing, and converting PDFs 100% offline.

Question 4

4. Why does my compressed file lose crispness or look blurry?

Accepted Answer

Compression reduces the resolution of internal PDF images to save size in MB. If you need high quality for printing blueprints or photos, select moderate compression level.

Question 5

5. Is PDFBlack 100% free or does it require registration?

Accepted Answer

PDFBlack is completely free, with no credit cards, no subscriptions, and no registration required.

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