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Model profile · OpenAI

GPT-5.6 Terra pricing

GPT-5.6 Terra costs $2.00 per 1M input tokens and $12.00 per 1M output tokens, with a 400K context window. Rates verified against the official OpenAI pricing page as of 2026-09-02.

Input

$2.00 /1M in

cached: $0.20

Output

$12.00 /1M out

6.0× the input rate

Context window

400K tokens

≈ 300,000 words

GPT-5.6 Terra at a glance

Input / 1M tokens $2.00
Cached input / 1M $0.20
Output / 1M tokens $12.00
Context window 400K tokens
≈ English words of context 300,000
Provider OpenAI
Price verified 2026-09-02

Source: OpenAI official pricing page. We re-verify every model monthly.

What GPT-5.6 Terra costs per month

Workload GPT-5.6 Terra monthly cost Per request
Side-project chatbot 30K req · 2,000 in · 500 out · 40% cached $256.80/mo $0.0086
Coding agent 500K req · 12,000 in · 1,500 out · 70% cached $13,440/mo $0.027
Bulk extraction 2,000K req · 800 in · 120 out · 20% cached $5,504/mo $0.0028

Computed from list prices verified 2026-09-02. Cache savings blend normal and cached input rates by the hit rate. Compare against every other model at your exact volumes on the API Cost Calculator.

How much context is 400K tokens?

About 300,000 English words — roughly 600 pages of text — or several large codebases. Filling the entire window once costs $0.800 in input tokens at list price, before the model generates a single output token. Count your real documents with the AI Token Counter.

Frequently asked questions

How much does GPT-5.6 Terra cost per million tokens?

GPT-5.6 Terra costs $2.00 per 1M input tokens and $12.00 per 1M output tokens, with cached input at $0.20. Rates are verified against OpenAI's official pricing page as of 2026-09-02.

How big is GPT-5.6 Terra's context window?

GPT-5.6 Terra ships a 400K token context window — roughly 300,000 English words, or about 600 pages of text. Filling the entire window once costs $0.800 in input tokens at list price.

Is GPT-5.6 Terra cheap or expensive compared to other models?

Among the 22 models we track, GPT-5.6 Terra ranks #14 on input price — cheapest is GPT-5 nano at $0.05, priciest is Claude Fable 5 at $10.00. At $2.00 per 1M input, GPT-5.6 Terra runs 40.0× the cheapest tier. Compare it head-to-head with its rivals on the model comparison pages.

What is cached input pricing on GPT-5.6 Terra?

GPT-5.6 Terra charges $0.20 per 1M cached input tokens — 10% of its $2.00 base input rate. If your requests repeat context (system prompts, documents, conversation history), prompt caching cuts the input portion of your bill accordingly. Model the exact savings on the API Cost Calculator.

More OpenAI models

Or see all rates on the Pricing Comparison.