GPT-5.5 Instant (June 2026) vs GPT-5.5 Instant (May 2026)
Humanity's Last Exam Humanity's Last Exam: Very hard expert questions across many fields, written to stump today’s models
GPT-5.5 Instant (June 2026)19.9
GPT-5.5 Instant (May 2026)21.6
Terminal-Bench 4.0 Terminal-Bench 4.0 · source setting 2: Agents use a terminal to complete executable coding, system administration and research tasks in the 4.0 suite
GPT-5.5 Instant (June 2026)12.6
GPT-5.5 Instant (May 2026)—
AutomationBench-AA AutomationBench-AA: Agents orchestrate SaaS workflows through APIs; objectives receive credit only when the task has no guardrail violation
GPT-5.5 Instant (June 2026)36.4
GPT-5.5 Instant (May 2026)—
| Benchmark | GPT-5.5 Instant (June 2026) | GPT-5.5 Instant (May 2026) |
|---|---|---|
| Humanity's Last Exam | 19.9 | 21.6 |
| Terminal-Bench 4.0 | 12.6 | — |
| AutomationBench-AA | 36.4 | — |
Specs
| Spec | GPT-5.5 Instant (June 2026) | GPT-5.5 Instant (May 2026) |
|---|---|---|
| Cost per task? | $0.69 | — |
| Speed, tok/s | 167 | — |
| Context | 400K | 400K |
| Weights | Closed | Closed |
| Released | Jun 2026 | May 2026 |
| See images | ✓ | ✓ |
| Read PDFs | ? | ? |
| Hear audio | — | — |
| Watch video | — | — |
| Call tools | ✓ | ? |
| Force a tool call | ? | ? |
| Return strict JSON | Partial | ? |
| Search the web | ? | ? |
| Run code | ? | ? |
| Use a computer | ? | ? |
What breaks when you switch
GPT-5.5 Instant (June 2026) → GPT-5.5 Instant (May 2026)
Nothing known.
GPT-5.5 Instant (May 2026) → GPT-5.5 Instant (June 2026)
Nothing known.