How Expensive Is Each OpenAI Model? (2026 Pricing Comparison)

How much does each OpenAI model cost in 2026? A full API pricing comparison of GPT-5.6 Sol, Terra and Luna against GPT-5.5, GPT-5.4, GPT-5 nano, Codex, embeddings, voice and image models — with real cost estimates per 1,000 requests.

OpenAI now offers models at radically different price points.

Standard short-context input pricing ranges from $0.05 per million tokens for GPT-5 nano to $30 per million tokens for GPT-5.5 Pro and GPT-5.4 Pro.

Output pricing has an even wider range, from $0.40 to $180 per million tokens.

OpenAI's most capable model is now GPT-6 Astra , priced at $10 input and $50 output per million tokens, with $1 cached input and $12.50 cache writes.

It has a 1,050,000-token context window, 128,000 maximum output tokens and a knowledge cutoff of 30 April 2026.

The GPT-5.6 family below it is divided into three models: GPT-5.6 Sol for the most difficult professional work.

GPT-5.6 Terra for a balance of intelligence and cost.

GPT-5.6 Luna for cost-sensitive, high-volume workloads.

OpenAI reduced the API prices of Terra and Luna on 30 July 2026 and cut GPT-5.6 Sol to a promotional rate of $4 input and $20 output per million tokens on 21 August 2026, available at least until 21 November 2026.

This comparison uses the prices available on 25 August 2026.

It covers API usage rather than ChatGPT subscription plans.

If you want capability rather than cost, see our best ChatGPT model guide and the GPT-5.6 vs Claude Fable 5 deep dive .