PVS vs Why3

PVS

6.6 #5 in Formal Verification Tools

About PVS

Why3

5.3 #30 in Formal Verification Tools

About Why3
PVSWhy3
Free planYesYes
Free trialNoNo
Paid fromFreeFree
Open sourceNoNo
PlatformsLinux, macOS, Windowsapi, Linux, self-hosted, Web, Windows
Free planYes—
Verification methodhybriddeductive
Supported formalismstheorem-provingcontracts
CounterexamplesYesYes
Proof artifactsYes—
Input languagesPVS specification language (typed higher-order logic)WhyML, micro-C, micro-Python, MLCFG, Coma
Deploymentself-hostedboth

Both are listed in Best Formal Verification Tools. On Freedom251, PVS scores higher on our published basis.