Tech riderRev. 20 Sept 2026

Why3

Ch 256.1of 33 Formal Verification Tools

1Runs onWeb, Linux, Windows
2CostsNot stated by the maker
3Verification methoddeductive
4Supported formalismscontracts
5CounterexamplesYes
6Input languagesWhyML, micro-C, micro-Python, MLCFG, Coma
7Deploymentboth

6 lines stated Written from the maker's own pages: why3.org

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Overview

Why3 is ranked #25 of 33 in formal verification tools on Specifiction. It runs on Web, Linux, Windows.

Compared on formal verification tools

Verification method: deductivewhy3.org
Supported formalisms: contractswhy3.org
Counterexamples: Yeswhy3.org
Input languages: WhyML, micro-C, micro-Python, MLCFG, Comawhy3.org
Deployment: bothwhy3.org

Best Why3 alternatives

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Where it ranks on Specifiction

Best Formal Verification Tools in 2026#25 of 33

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