Why is my PDF so large? What compression removes
Where the bytes in a PDF go, why photos dominate, and a worked example that takes a 34 MB page to 437 KB without touching the text.
Guides
How PDF compression, file metadata, redaction and in-browser processing actually work, with worked examples and the tools to do each job.
How to check if a file tool uploads your files
Two tests you can run in a few minutes with your browser's developer tools: watch the network while the tool works, then run it offline.
What a photo's metadata gives away, and how to remove it
A 34 MB press photo carried 40 KB of hidden data, including two serial numbers. What EXIF, XMP and IPTC hold, and how to strip them.
How to redact a PDF so the text is really gone
A black box over text is not a redaction. A test file shows why, where else a PDF hides content, and a checklist to run before you send.
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