Humanity’s Last Exam
Stable HLE — full set ↗Tools enabled- GPT-5.5 Pro:
- GPT-6 Astra:
Compare models
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Updated: Data as of:
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Model specifications
| Specifications |  GPT-5.5 ProOpenAI | GPT-6 AstraOpenAI |
|---|---|---|
| Provider | ||
| Context sizetokens | 922,000 | 1,000,000 |
| Cutoff date | Not reported | 2026-04-30 |
| Input costUSD / 1M tokens | $30.00 | $10.00 |
| Output costUSD / 1M tokens | $180.00 | $50.00 |
| Max outputtokens | 128,000 | 128,000 |
| LatencyTTFT · seconds | Not reported | 365.127 |
| Speedtokens / sec | Not reported | 70.564 |
Benchmark performance
1 shared benchmark comparisons. Versions and setups matched.
GPT-5.5 ProGPT-6 Astra
