Catch the obvious weaknesses first
Before a resume reaches a person, it should clear a few basics: the right length, real contact details, achievements backed by numbers, strong action verbs, clear sections, and none of the clichés recruiters have read a thousand times. This checker tests all of those and scores the result, with a specific fix for anything it flags.
Heuristics, run privately
The checks are rules of thumb rather than a definitive judgment — the job you are applying for always matters more. But they reliably catch the avoidable problems, and because it all runs in your browser, your resume is never uploaded.