Synonyms of foolproof

foolproof

adjective

as in perfect

done, made, or planned so well that nothing can go wrong

a foolproof plan

DNA fingerprinting gives police a virtually foolproof way to link a suspect to a crime scene.

Related Words

• perfect
• flawless
• reliable
• infallible
• sure
• unfailing
• unerring
• certain
• inerrant
• faultless
• dependable
• impeccable
• errorless

Dissimilar Words

• defective
• imperfect
• faulty
• flawed
• unreliable
• undependable
• fallible

Example Sentences

Recent Examples of foolproof

When in doubt, these sunglasses make a truly timeless, foolproof gift. — Genevieve Cepeda, InStyle, 21 Oct. 2026

But remember, says Reed, no prevention strategy is foolproof. — Andee Tagle, NPR, 15 Oct. 2026

There’s no foolproof security system to ensure that those who buzz in with a badge are necessarily the badge holders. — Laurent Belsie, Christian Science Monitor, 7 Oct. 2026

Scoring more than two goals per period is a pretty foolproof way to win hockey games. — Corey Masisak, Denver Post, 4 Oct. 2026