Fuzzilli vs OneFuzz: 2026 Comparison
Fuzzilli is a free offensive security tool. OneFuzz is a free offensive security tool. Compare features, ratings, integrations, and community reviews side by side to find the best offensive security fit for your security stack.
CST VerdictBased on our analysis of available product data, here is our conclusion:
JavaScript security teams and browser vendors hunting for engine-level vulnerabilities should use Fuzzilli; it's purpose-built to find bugs that static analysis and functional testing miss. The tool has been battle-tested by Google and Mozilla, with 2,080 GitHub stars reflecting real adoption in production fuzzing pipelines. Skip this if you're looking for a general-purpose application fuzzer or need to test non-engine JavaScript code; Fuzzilli's value collapses outside the narrow domain of JavaScript engine development.
Development teams embedding security into the build pipeline should use OneFuzz to catch memory safety bugs before production without waiting for dedicated security staff to write test cases. The platform's self-hosted fuzzing-as-a-service model lets developers run continuous automated fuzzing on their own infrastructure for free, eliminating dependency on cloud-based tools and third-party services. Skip this if your organization needs guided vulnerability triage or remediation workflow integration; OneFuzz surfaces crashing inputs and generates test cases, but assumes you have the expertise to turn those findings into fixes.
