Grok 4
xAI's 2025 model — superseded by Grok 4.7
Verdict
Three releases behind now (4.5, 4.6, then 4.7). There is no remaining reason to build new on Grok 4 specifically — go straight to 4.7.
Other Text Generation & Reasoning
- GPT-6 AstraProduction
OpenAI's most capable model — 1.05M context, 128K output
- GPT-6.1 SolProduction
The OpenAI default — near-Astra quality at a fifth of the price
- GPT-6 LunaProduction
OpenAI's efficient tier — $0.10/$0.50 with the full 1.05M context
- GPT-5.6Superseded
Previous OpenAI family — Sol/Terra/Luna tiers, superseded by GPT-6
- GPT-5Superseded
OpenAI's 2025 flagship — two families back now
- GPT-5 miniSuperseded
OpenAI's 2025 cost-efficient model — superseded by GPT-6 Luna