GPT-5.5 vs T3MP3ST
GPT-5.5 (paid, AI Score 9.4/10) vs T3MP3ST (free, AI Score 7.8/10). Side-by-side pricing, features, pros and cons, and which to pick.
The verdict
- →overall capability matters more than price (AI Score 9.4 vs 7.8)
- →you want our editor's pick for this category
Side-by-side specs
| Spec | GPT-5.5 | T3MP3ST |
|---|---|---|
| Category | Coding | Coding |
| Pricing model | paid | free |
| Headline pricing | API: $5/$30 per 1M tokens (in/out). ChatGPT Plus $20/mo, Pro $200/mo | Free, open source (AGPL-3.0) — you pay for the underlying AI agent's API usage |
| Free tier | No free API tier. Free ChatGPT users get GPT-4o, not GPT-5.5. | Entire project is free and open source under AGPL-3.0; the only real cost is the token/subscription spend of whatever AI agent you plug in. |
| AI Score | 9.4/10 | 7.8/10 |
| Best for | — | — |
| Editor's pick | ✓ Yes | — |
| Use cases | — | — |
| Date added | 2026-05-02 | 2026-07-05 |
Pros and cons
GPT-5.5
Coding · paid
Pros
- ✓Top-of-class coding and reasoning benchmarks — measurably ahead of GPT-5 and competitive alternatives
- ✓True agentic capability with tool use, self-correction, and multi-step task completion
- ✓272K context handles entire codebases without chunking workarounds
- ✓Codex integration turns it into an autonomous software engineer inside ChatGPT
Cons
- ×API pricing is premium — $30/M output tokens adds up fast for heavy usage
- ×No free tier for the API; ChatGPT Free users are stuck on GPT-4o
- ×Slower inference than lighter models like GPT-4o-mini for simple tasks
- ×Closed-source with no self-hosting option — full vendor lock-in to OpenAI
T3MP3ST
Coding · free
Pros
- ✓Free and fully open source (AGPL-3.0) — the orchestration layer is inspectable, which matters for a tool aimed at sensitive targets
- ✓Agent-agnostic: leverages capable coding agents you may already pay for (Claude Code, Codex) instead of a weaker bundled model
- ✓Multi-agent approach can parallelize recon and exploitation work that would be tedious to drive by hand in a single session
- ✓Comes from a well-known red-teaming researcher, so the workflow is designed by someone fluent in offensive security
Cons
- ×Early-stage GitHub framework, not a polished product — expect setup friction, thin docs, and self-reported benchmarks rather than independent validation
- ×Real cost is hidden: fanning out multiple agents can burn through API tokens or agent subscription limits quickly
- ×AGPL-3.0 copyleft complicates embedding it in closed-source or commercial security products
- ×Dual-use by nature — only appropriate for authorized testing, and autonomous runs still surface false positives that need expert triage
FAQ
Is GPT-5.5 better than T3MP3ST? ▾
GPT-5.5 scores 9.4/10 in our evaluation versus T3MP3ST at 7.8/10. GPT-5.5 edges ahead overall, but "better" depends on your use case — see the verdict block above.
Does GPT-5.5 or T3MP3ST have a free tier? ▾
Both offer free access. GPT-5.5: No free API tier. Free ChatGPT users get GPT-4o, not GPT-5.5.. T3MP3ST: Entire project is free and open source under AGPL-3.0; the only real cost is the token/subscription spend of whatever AI agent you plug in..
Should I choose GPT-5.5 or T3MP3ST in 2026? ▾
If overall capability matters more than price (AI Score 9.4 vs 7.8) pick GPT-5.5. If budget is the constraint pick T3MP3ST. Both are credible — neither is a wrong choice.
Related comparisons
Updated 2026-07-05. Spec data sourced from official product pages and tracked in our public directory at /tools.