OpenAI’s GPT-6 Sol (Max) achieves 7.7% net improvement while cutting API costs in half

OpenAI released GPT-6 Sol (Max) on September 22, 2026, posting a +7.7% net improvement across more than 4,000 real-world agentic sessions on the Agent Arena leaderboard while pricing its API at $2 per million input tokens and $10 per million output tokens, roughly half the cost of predecessor GPT-5.6 Sol (xHigh). The model ranks #6 on the leaderboard, up from GPT-5.6 Sol's #8, and scored +11.4% on the Confirmed Success metric (#4 overall) and 68.8% on DeepSWE v1.1, trailing Anthropic's Claude Fable 5 configurations but at around 80% less cost, per OpenAI. OpenAI launched GPT-6 Luna alongside Sol the same day, both joining GPT-6 Astra in the GPT-6 family.

OpenAI official logo public domain, Wikimedia Commons — CryptoBriefing brand treatment OpenAI’s GPT-6 Sol Max achieves 7.7% net improvement while cutting API costs in half The new model climbs to 6 on the Agent Arena leaderboard at roughly half the price of its predecessor, intensifying the AI pricing war with Anthropic. OpenAI https://cryptobriefing.com/markets/openai/ just made its most aggressive cost-performance play yet. GPT-6 Sol Max , released on September 22, 2026, posted a +7.7% net improvement across more than 4,000 real-world agentic sessions on the Agent Arena leaderboard, while operating at roughly half the API cost of its predecessor. The model now sits at 6 on the leaderboard, up from the 8 spot held by GPT-5.6 Sol xHigh , which managed only a +6.2% improvement. The numbers behind Sol’s leap GPT-6 Sol’s API pricing lands at $2 per million input tokens and $10 per million output tokens. That represents a 50% reduction from GPT-5.6 rates, a pricing move that transforms the economics of running agentic workflows at scale. On the Confirmed Success metric, which measures tasks definitively completed rather than partially attempted, GPT-6 Sol scored +11.4% and ranked 4 overall. That’s a stronger showing than its composite leaderboard position suggests, indicating the model is particularly reliable when tasks demand completion rather than approximation. On the DeepSWE v1.1 benchmark, a widely tracked measure of software engineering capability at maximum effort, GPT-6 Sol posted a score of 68.8%. That figure trails the top results from Anthropic https://cryptobriefing.com/markets/anthropic/ ’s Claude Fable 5 configurations. But context matters here: OpenAI claims Sol achieves its DeepSWE performance at around 80% less cost than the highest-performing Claude counterparts. AI, tech, and the markets they move—in one daily briefing. Daily. Free. Join 34,000+ readers across crypto, finance, and policy. GPT-6 family expands its roster Sol didn’t arrive alone. OpenAI launched GPT-6 Luna alongside it on the same day, with both models joining GPT-6 Astra, which had already been released as part of the broader GPT-6 family. GPT-6 Sol and Luna specifically target scalable, cost-effective applications, including agentic workflows, professional automation pipelines, and always-on AI infrastructure. The pricing war heats up Anthropic’s Claude Opus 5 and Claude Fable 5 remain formidable, with top-tier DeepSWE scores that exceed Sol’s 68.8%. The AutomationBench results, where Sol reportedly completed tasks at lower cost than certain Claude Opus 5 configurations, underscore the strategic intent: OpenAI is targeting the cost-per-completed-task metric rather than absolute benchmark rankings. Disclosure: This article was edited by Diego Almada Lopez. For more information on how we create and review content, see our Editorial Policy https://cryptobriefing.com/editorial-policy/ .