xAI

xAI is Elon Musk's AI company, founded in 2023 and integrated with X (formerly Twitter) for real-time data. On July 8, 2026 it released Grok 4.5, its first model built specifically for coding and agentic work, on the 1.5 trillion parameter V9 foundation (up from Grok 4.3's V8) and trained on real coding-agent data. Grok 4.5 lands fourth on the Artificial Analysis Intelligence Index, above every open-weight model and every Gemini model, at a price more than 60% below Claude Opus 4.8 or GPT-5.5. It leads Opus 4.8 on the provider-harness DeepSWE 1.0 score and on Terminal-Bench 2.1 (83.3) while trailing it on the neutral DeepSWE 1.1 run and on SWE-Bench Pro (64.7). API pricing is $2 input / $6 output per 1M tokens, with cached input at $0.50 and a higher-context surcharge above 200K tokens. xAI narrowed the context window to 500K tokens to focus the model on coding, and says it plans to train new models from scratch on a monthly cadence through the end of 2026.