Gemini 4 Argon
Google’s stable flagship — multimodal, with a 1M unified window
Verdict
Generally available since October 2026, and the end of the odd period when Flash outclassed Pro. $2/$10 per million tokens through November 30, then $4/$20 from December 1, so plan around the higher number. The 1M window is shared by input and output, with 65,536 output tokens by default and more with long decode.
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-6.1 TerraProduction
OpenAI’s mid tier — half of Sol’s price with the full 1.05M context
- 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Previous OpenAI family — Sol/Terra/Luna tiers, superseded by GPT-6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