Best Formal Verification Tools in 2026
Updated
In short: Rocq is ranked #1 of 33 as of 4 October 2026, ahead of PVS and Z3. The best-ranked option with a free plan is PVS.
Formal verification tools help you state software properties and examine whether implementations satisfy them. Compared on supported formalisms and input languages, the entries vary in the kinds of problems they address; verification method, counterexamples, and proof artifacts show other useful distinctions. Deployment, free-plan availability, and paid-from pricing round out the comparison. Rocq, Isabelle, and PVS appear at the start of the ranking, with ACL2, Z3, Frama-C, Lean, and K Framework also among the first entries. Consider which languages and forms of evidence fit your work, then weigh the listed methods and plan details against the systems you need to verify.
33 formal verification tools ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
#1 Rocq Top pick · 7.4 Free plan · Free
#2 PVS Runner-up · 7.3 Free plan · Free
#3 Z3 Also great · 7.3 Free plan · Free- Free plan extensionLinuxmacOSWebWindows
- Free plan
- Yes
- Verification method
- deductive
- Supported formalisms
- theorem-proving
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatformsFree About RocqVisit site - Free plan LinuxmacOSWindows
- Free plan
- Yes
- Verification method
- hybrid
- Supported formalisms
- theorem-proving
- Counterexamples
- Yes
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatformsFree About PVSVisit site - Free plan AndroidapiLinuxmacOSself-hostedWebWindows
- Free plan
- Yes
- Supported formalisms
- theorem-proving
- Counterexamples
- Yes
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatformsFree About Z3Visit site - Free plan LinuxmacOSself-hostedWindows
- Free plan
- Yes
- Verification method
- deductive
- Supported formalisms
- theorem-proving
- Counterexamples
- Yes
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatforms - Free plan LinuxmacOSWindows
- Free plan
- Yes
- Verification method
- model-checking
- Supported formalisms
- temporal-logic
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatformsFree About SPINVisit site - Free plan LinuxmacOSWindows
- Free plan
- Yes
- Verification method
- model-checking
- Supported formalisms
- invariants
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - Free plan apiLinuxmacOSWindows
- Free plan
- Yes
- Verification method
- model-checking
- Supported formalisms
- invariants
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - LinuxmacOSself-hostedWindows
- Free plan
- Yes
- Verification method
- deductive
- Supported formalisms
- theorem-proving
- Counterexamples
- Yes
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatforms - LinuxmacOSWindows
- Free plan
- Yes
- Verification method
- hybrid
- Supported formalisms
- contracts
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WebWindowsmacOSLinux
- Free plan
- Yes
- Verification method
- deductive
- Supported formalisms
- theorem-proving
RecognisedDocumentedFree planPlatforms - WebWindowsmacOSLinux
- Verification method
- deductive
- Supported formalisms
- theorem-proving
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Free plan
- Yes
- Verification method
- model-checking
- Supported formalisms
- contracts
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Verification method
- hybrid
- Supported formalisms
- invariants
- Counterexamples
- Yes
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatforms - WebWindowsmacOSLinux
- Supported formalisms
- theorem-proving
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Free plan
- Yes
- Verification method
- deductive
- Supported formalisms
- contracts
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Free plan
- Yes
- Verification method
- hybrid
- Supported formalisms
- temporal-logic
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Free plan
- Yes
- Verification method
- symbolic
- Supported formalisms
- temporal-logic
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Free plan
- Yes
- Verification method
- deductive
- Supported formalisms
- contracts
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Free plan
- Yes
- Verification method
- hybrid
- Supported formalisms
- contracts
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Verification method
- deductive
- Supported formalisms
- theorem-proving
RecognisedDocumentedFree planPlatforms - WindowsLinuxmacOS
- Verification method
- hybrid
- Supported formalisms
- theorem-proving
RecognisedDocumentedFree planPlatforms - WindowsLinux
- Free plan
- Yes
- Supported formalisms
- theorem-proving
- Counterexamples
- Yes
- Proof artifacts
- Yes
RecognisedDocumentedFree planPlatforms - LinuxmacOS
- Free plan
- Yes
- Verification method
- hybrid
- Supported formalisms
- theorem-proving
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Verification method
- deductive
- Supported formalisms
- contracts
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms - WindowsmacOSLinux
- Verification method
- hybrid
- Supported formalisms
- invariants
- Counterexamples
- Yes
RecognisedDocumentedFree planPlatforms
Is your app on this list?
Numbered spots on this list can be sponsored. They are labelled, and the editorial order and scores never change for payment.
Questions about this list
Which formal verification tool is ranked first on Everything Xiaomi?
Rocq is ranked #1 of 33 with a score of 7.4. PVS is second and Z3 third.
How many of these have a free plan?
7 of the 25 on this page publish a free plan on their own pricing pages.
How is this list ranked?
Ranked on what each maker publishes: documentation depth, a free tier and the platforms it runs on. Paid placements never change a rank.