PDF File Inspector
Read low-level PDF signatures and flags.
Inspect binary PDF internals instantly in your browser: header version, linearized flag, xref count.
Calculator Inputs
About File Inspector
Read low-level PDF signatures and flags.
Reads the raw first KB and last 2 KB of the file to surface format-signature facts without opening the document.
Where it is used
Preflight downloads, QA export pipelines, corruption triage.
How to use the File Inspector
- PDF File — select a file (application/pdf,.pdf) — Up to 50 MB. Byte-reading happens locally..
- Calculate — press the Calculate button to see the result instantly above.
Formula
Header + trailer byte scanning for %PDF-x.y, /Linearized, /Size.
Examples
Example
Result: Header: %PDF-1.7 · Size: 4123 · 2.1 MB
Frequently Asked Questions
- Object count meaning?
- The /Size entry — an upper bound on indirect object numbers, useful for sanity checks.