Paste a COBOL copybook and see every field's storage length and byte offset, computed from its PICTURE clause and usage.
Handles common PIC clauses, OCCURS, REDEFINES, and COMP/COMP-3 sizing. It does not implement the full COBOL grammar (nested REDEFINES chains and COMP-1/2 floats are out of scope), and group items without their own PICTURE show as a group, not a computed total, rather than guessing wrong.