Counts are this browser's (all its tabs). zKillboard's limit is the page's own, to stay polite; ESI's are CCP's.
Threat Vector
For EVE Online: who's in system, what they fly, and how to beat them.
Everyone in system: select all, Ctrl+C
Ships within ~14 AU: Ctrl+A, Ctrl+C
Pilot Analyzer
Enter a pilot's name and, optionally, a ship type (from a D-Scan, or typed manually). Leave the ship blank and it'll sample their recent losses to guess which hull they fly most.
Fit Analyzer
Paste a fit copied from the EVE client's fitting window (Ctrl+A, Ctrl+C in the Fitting window) or exported from pyfa as EFT format. Shows the same cards as the Pilot Analyzer, just for any fit you give it directly instead of a specific killmail.