Best Fuzz Testing Software in 2026
Updated
In short: Mayhem is ranked #1 of 19 as of 3 October 2026, ahead of OSS-Fuzz and ClusterFuzz. The best-ranked option with a free plan is OSS-Fuzz. The lowest first paid tier on this page is Mayhem at $236/mo.
19 fuzz testing software ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
| # | Platform | Score | Why | From | Free plan | Paid from | Input generation methods | |
|---|---|---|---|---|---|---|---|---|
| 1 | Mayhem | 8.9 | RecognisedAPIDocumented | $236/mo | — | — | hybrid | View |
| 2 | OSS-Fuzz | 7.4 | RecognisedAPIDocumented | Free | Yes | — | mutation | View |
| 3 | ClusterFuzz | 7.4 | RecognisedAPIDocumented | Free | — | — | mutation, generation, hybrid | View |
| 4 |  AFL++ | 7.2 | RecognisedAPIDocumented | €1666.67/mo | Yes | — | mutation | View |
| 5 |  Jazzer | 6.7 | RecognisedAPIDocumented | Free | Yes | — | mutation, generation | View |
| 6 | FuzzForge | 6.5 | RecognisedAPIDocumented | — | Yes | — | generation | View |
| 7 | EvoMaster | 6.4 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 8 |  EvoMaster | 6.3 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 9 |  Fuzzilli | 6.1 | RecognisedAPIDocumented | — | — | — | mutation, generation, hybrid | View |
| 10 |  cargo-fuzz | 6.1 | RecognisedAPIDocumented | Free | — | — | mutation, generation, hybrid | View |
| 11 |  Metalware | 5.9 | RecognisedAPIDocumented | — | — | — | generation and mutation, with symbolic input generation | View |
| 12 |  Netzob | 5.8 | RecognisedAPIDocumented | — | Yes | — | mutation, generation | View |
| 13 |  boofuzz | 5.8 | RecognisedAPIDocumented | — | Yes | — | hybrid | View |
| 14 |  Schemathesis | 5.7 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 15 |  Fuzzware | 5.6 | RecognisedAPIDocumented | — | — | — | mutation | View |
| 16 |  Csmith | 5.5 | RecognisedAPIDocumented | — | Yes | — | generation | View |
| 17 |  Wfuzz | 5.3 | RecognisedAPIDocumented | — | Yes | — | generation | View |
| 18 |  Onyx Launcher | 5.3 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 19 |  Fuzzinator | 4.9 | RecognisedAPIDocumented | — | — | — | generation, mutation | View |
Is your platform 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 fuzz testing software is ranked first on Inferse?
Mayhem is ranked #1 of 19 with a score of 8.9. OSS-Fuzz is second and ClusterFuzz third.
How many of these have a free plan?
6 of the 19 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, Mayhem has the lowest first paid tier we found: $236/mo.
How is this list ranked?
Ranked on what each maker publishes, open and connectable first: a public API, open-source code, the depth of its documentation and a free tier to try it on. Model lists are sorted by the figure in their title, exactly as each provider publishes it. Paid placements never change a rank.