Summary
On August 21, 2026, OpenAI reduced developer pricing for its frontier GPT-5.6 Sol model: input dropped from $5 to $4 per million tokens (down 20%), output from $30 to $20 (down 33%), and cached input from $0.50 to $0.40 (down 20%). OpenAI listed the rate as promotional through at least November 21, 2026, applying to the pay-as-you-go API, Codex credits, and eligible ChatGPT Work plans, while Pro, Plus, and Business subscriptions are unchanged.
What changed
OpenAI cut GPT-5.6 Sol API pricing: input $5 to $4 per million tokens (down 20%), output $30 to $20 (down 33%), and cached input $0.50 to $0.40 (down 20%), promotional through at least November 21, 2026. The cut applies to the pay-as-you-go API, Codex credits, and eligible ChatGPT Work plans; Pro, Plus, and Business subscriptions are unchanged.
Why it matters
A sharp cut on a frontier model, especially the 33% output-token reduction, directly lowers the marginal cost of agentic and coding workloads that burn output tokens, and pressures competitors' per-token pricing. Scoping the cut to the API, Codex, and Work plans signals OpenAI defending developer and agent usage specifically rather than consumer subscriptions.
Evidence excerpt
Input went from $5 to $4 per million tokens (down 20%), output from $30 to $20 (down 33%) and cached input from $0.50 to $0.40 (down 20%)... promotional and available through at least November 21, 2026. The reduction applies to the pay-as-you-go API, to Codex credits and to eligible ChatGPT Work plans.