Convert a PDF into PDF/A, the ISO-standardised subset of PDF meant for long-term archiving. PDF/A requires everything needed to display the document to be contained inside the file, so fonts are embedded and features that depend on the outside world - external references, JavaScript, encryption - are removed. Many archives, courts and government submission systems require it.
Usually it looks the same. Where it changes, the cause is generally a font that was not embedded and had to be substituted, or transparency being flattened for the stricter conformance levels.
The tool offers three: PDF/A-1b, PDF/A-2b and PDF/A-3b. Take whichever the receiving system asks for. PDF/A-1b is the oldest and most widely accepted but the most restrictive; PDF/A-2b allows more, including transparency and JPEG 2000 images; PDF/A-3b additionally permits embedded source files. If nobody has specified one, PDF/A-2b is the sensible default.
No. PDF/A forbids encryption, so remove the password first with Remove PDF Password.
No - conversion does not add text. Run OCR PDF first if the archived document needs to be searchable, which most archival requirements expect.
The signature is stripped during conversion, and the tool warns you before it starts. This is unavoidable: PDF/A rewrites the file structure, which is precisely the change a signature exists to detect. Convert first and sign the archival copy afterwards.
Files are uploaded over an encrypted connection and processed on CoonTool's own server, not in your browser. The working copy is deleted automatically once the job is done, and in any case within 24 hours. Nothing is stored permanently and no account is required.