X Ai
Grok 4.20
Grok 4.20 is xAI's newest flagship model with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherance, delivering consistently precise and truthful responses. Reasoning can be enabled/disabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens)
- Input / 1M tokens
- $2.00
- Output / 1M tokens
- $6.00
- Context window
- 2M tokens
- Provider
- X Ai
- Cached input / 1M
- $0.200
- Knowledge cutoff
- 2025-09-01
Performance
Median streaming throughput and first-token latency measured by Artificial Analysis.
- Output tokens / sec
- 177 t/s
- Time to first token
- 15.26s
Benchmarks
Intelligence, coding, and math indexes plus the underlying evaluation scores.
- Intelligence Index
- 49
- Coding Index
- 41
- Math Index
- —
- MMLU-Pro
- —
- GPQA
- 91.1%
- HLE
- 32.2%
- LiveCodeBench
- —
- SciCode
- 45.6%
- MATH-500
- —
- AIME
- —
Benchmarks via Artificial Analysis