create
Add a Document Manifest
Prepend an inventory page recording what a document is, with a checksum.
Runs in your browser
How it works
The manifest records the page count, page sizes, file size, title and author, plus a SHA-256 checksum of the document exactly as it arrived. Anyone who later has the same file can compute the same checksum and confirm nothing changed. The hash covers the incoming document rather than the finished one, because a file cannot meaningfully contain a checksum of itself.
Related tools
Questions
- What does the checksum prove?
- That two files are byte-for-byte identical. It says nothing about who made a document or when.
- Why hash the original rather than the result?
- A file cannot contain a checksum of itself. The manifest records the document it describes.
- Is this a legal seal?
- No. It is a record, useful for archives and handovers, not a certification.