Which is cheaper, GPT-5.6 Terra or GPT OSS 20B?
As of August 20, 2026, GPT OSS 20B is 98% cheaper on blended LLM API pricing. GPT OSS 20B costs $0.05 per million input tokens and $0.20 per million output tokens ($0.25 blended 1M-in + 1M-out). GPT-5.6 Terra costs $2.00 / $12.00 per million tokens ($14.00 blended). Sources: https://developers.openai.com/api/docs/pricing and https://developers.openai.com/api/docs/pricing. The cheapest LLM for your app still depends on how many output tokens you generate.
How much does GPT-5.6 Terra vs GPT OSS 20B cost per million tokens?
GPT-5.6 Terra OpenAI API pricing is $2.00 input and $12.00 output per million tokens via OpenAI. GPT OSS 20B OpenAI API pricing is $0.05 input and $0.20 output per million tokens via OpenAI. Use those four numbers, not ChatGPT Plus or Claude Pro subscription prices, when you are comparing APIs.
Which is better for coding, GPT-5.6 Terra or GPT OSS 20B?
GPT-5.6 Terra has a published SWE-bench Verified score of 75.2%. GPT OSS 20B does not have that eval on this page yet.
What is the context window for GPT-5.6 Terra vs GPT OSS 20B?
GPT-5.6 Terra supports a 1M token context window, while GPT OSS 20B supports 131K tokens. GPT-5.6 Terra offers a larger context window. Filling a larger window bills more input tokens, so the cheaper-per-million model can still cost more on long documents.
Which model performs better on benchmarks, GPT-5.6 Terra or GPT OSS 20B?
GPT-5.6 Terra leads on 8 of 9 shared benchmarks versus GPT OSS 20B's 1 wins. Check the comparison table for GPQA Diamond, SWE-bench, MMLU, HLE, and the other evals we track. Token price and benchmark score together are the usual LLM comparison, not either number alone.
Is GPT-5.6 Terra or GPT OSS 20B better for production use?
Both GPT-5.6 Terra and GPT OSS 20B are production API models. For cost-sensitive production traffic, GPT OSS 20B has better economics on the blended 1M-in + 1M-out scale. For maximum capability, weight the benchmark table for your domain. Many production stacks route cheap models for drafts and a frontier model for the hard turn, which is usually cheaper than sending everything to the expensive API.
Can I switch between GPT-5.6 Terra and GPT OSS 20B in my app?
Yes. Call GPT-5.6 Terra through OpenAI and GPT OSS 20B through OpenAI with separate API keys, or through a gateway that already wraps both. Keep prompts in tokens, not characters, when you estimate the invoice. AnotherWrapper templates can swap providers without rewriting auth and billing.
How accurate is this GPT-5.6 Terra vs GPT OSS 20B pricing data?
List rates are the latest published OpenAI API pricing and OpenAI API pricing, quoted per million tokens. Official rate sheets: https://developers.openai.com/api/docs/pricing and https://developers.openai.com/api/docs/pricing. Prompt caching, batch APIs, and committed-use discounts can change the invoice. Benchmark scores are from official publications and independent evals, updated as new numbers land.
What is the output token limit for GPT-5.6 Terra and GPT OSS 20B?
GPT-5.6 Terra supports up to 128K output tokens per request, while GPT OSS 20B supports up to 33K output tokens. Output tokens are usually the expensive half of API pricing, so a higher max output cap is a capability, not a discount.
Which model has better throughput, GPT-5.6 Terra or GPT OSS 20B?
GPT-5.6 Terra runs at approximately 34.88545641142904 tokens/second while GPT OSS 20B runs at 1000 tokens/second. GPT OSS 20B is faster in raw throughput. Throughput (tokens per second) and time-to-first-token are why two models with the same per-million-token price can still feel different in chat and agents.
How do I switch the models in this GPT-5.6 Terra vs GPT OSS 20B comparison?
Use the model pickers at the top of this LLM comparison. Search any model in the index and the URL updates. Open GPT-5.6 Terra or GPT OSS 20B from the sidebar for the single-model API pricing page, or go back to the LLM pricing table to sort by cheapest blended cost.
