SeaSponge vs Heeler Runtime Threat Modeling: 2026 Comparison
SeaSponge is a free threat modeling tool. Heeler Runtime Threat Modeling is a commercial threat modeling tool by Heeler. Compare features, ratings, integrations, and community reviews side by side to find the best threat modeling fit for your security stack.
CST VerdictBased on our analysis of NIST CSF 2.0 coverage, core features, company size fit, deployment model, here is our conclusion:
Teams building threat models for the first time or teaching threat modeling to developers should start with SeaSponge; its web-based interface and visual-first design eliminate the friction that kills adoption of desktop tools or spreadsheet-based approaches. The free pricing and 281 GitHub stars signal active maintenance and community use, rare for threat modeling tools that usually languish after launch. Skip this if your team needs deep integration with your existing security tools or collaborative features at enterprise scale; SeaSponge prioritizes simplicity over extensibility.
