Free
Free
KeY is open-source research software available via download links on the project site.
- Access
- KeY is open-source research software available via download links on the project site.
KeY
● Identity checkedCode · Vendor site 2026-10-04
The KeY Project provides formal verification and symbolic debugging tools for Java programs. Researchers and educators use KeY to prove correctness against JML specifications, generate tests, and teach program verification with downloadable tooling and course material.
- Category
- Code
- Free access
- KeY is open-source research software available via download links on the project site.
- API access
- Not confirmed as a hosted API; KeY ships as desktop verification and debugging tools.
Is KeY right for you?
A good fit for
Universities, formal methods researchers, and Java engineers who need deductive verification beyond unit testing.
Before you choose
Support is community- and academia-oriented; the site does not publish commercial SaaS subscription tiers.
Java formal verification
The KeY Project homepage promotes deductive verification, symbolic debugging, and teaching resources for correct Java software.
What it can do
Features & capabilities
Unknown is different from unavailable. Each fact carries its own evidence.
| Capability | Value | Evidence | Checked |
|---|---|---|---|
| JML verification | Homepage describes augmenting Java programs with JML specifications and proving behavior with KeY. | Facts sourced | 2026-10-04 |
| Symbolic debugger | Site highlights a Symbolic Execution Debugger with execution-flow visualization. | Facts sourced | 2026-10-04 |
| Teaching resources | Navigation advertises KeY for teaching with course materials and symposium events. | Facts sourced | 2026-10-04 |
Understand the total cost
KeY pricing & plans
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Frequently asked questions
What is KeY used for?
The KeY Project provides formal verification and symbolic debugging tools for Java programs. Researchers and educators use KeY to prove correctness against JML specifications, generate tests, and teach program verification with downloadable tooling and course material.
Does KeY have a free plan?
KeY is open-source research software available via download links on the project site.. This record lists ongoing free access; check the plan limits before starting.
How much does KeY cost?
No paid monthly price is listed; this record treats the product as free to start. See the plan cards for entitlements, billing commitments and seat minimums.
Can I use KeY through an API?
Not confirmed as a hosted API; KeY ships as desktop verification and debugging tools.. API access and subscription access may have different terms; consult the linked sources.
What should I check before choosing it?
Support is community- and academia-oriented; the site does not publish commercial SaaS subscription tiers.
Price history
No retained pricing changes yet. A current price alone does not establish a historical trend.
How this profile is supported
Identity and profile
Reviewed vendor source
Read original source ↗Facts apply to the named version and check date. Send a sourced correction if something changed.