xAI Launches Grok 4.5 to Challenge Anthropic
Elon Musk-founded AI startup xAI has been working to compete with industry heavyweights including OpenAI and Anthropic. As large language models gain traction among businesses and developers, computational efficiency and deployment costs have become key competitive battlegrounds. xAI’s new model aims to disrupt the market with greater token efficiency and lower pricing while directly challenging rival flagship products.
xAI launched the Grok 4.5 large language model and made its API available on July 16, 2026. Built on a 1.5-trillion-parameter base model and trained using GB300 systems, it offers a 500K context window and twice the token efficiency of comparable models. Grok 4.5 is priced at $2 per million input tokens and $6 per million output tokens, positioning it against Anthropic’s Opus 4.7.
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The history behind this eventxAI Launches Grok 4.6 With Frontier Scores, Lower Prices
xAI developed Grok 4.6 as a flagship model for long-running agents, software development and knowledge work, extending Elon Musk’s push to challenge OpenAI and Anthropic at the AI frontier. Rather than relying on a new pretraining run, the company said the gains came mainly from post-training with supervised fine-tuning and reinforcement learning. The release underscores an intensifying industry cost race, showing that stronger reasoning and agent performance may not always require a larger base model or a proportionate increase in computing expenditure.
Released on Aug. 12, 2026, Grok 4.6 offers a 500,000-token context window and scored 61 on the Artificial Analysis Intelligence Index, level with OpenAI’s GPT-5.6 Sol. Its DeepSWE 1.1 result reached 65.9%, while GDPVal-AA v2 registered 1,753 Elo. xAI priced the standard API at $2 per million input tokens and $6 per million output tokens, compared with $5 and $30, respectively, for GPT-5.6 Sol. The model launched through the xAI API, Grok Build, Cursor, OpenRouter, Vercel and Cloudflare.
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