GPT-6.1 Terra vs Claude Sonnet 5.5

API price, context window and output limit for GPT-6.1 Terra and Claude Sonnet 5.5 from Kingy's checked data, and what common workloads cost on each. Every price shows when Kingy last checked it.

At a glance

Verdict: Kingy cannot confirm both prices right now. In Kingy's tests, GPT-6.1 Terra gave fewer wrong answers on the AI Accuracy Index (6.0% against 10.4%) with a similar share right; both passed 20/20 on Kingy's coding and data tasks, and GPT-6.1 Terra's bill was 3.3× lower ($0.026 against $0.086).

GPT-6.1 Terra: price is not confirmed right now, so Kingy shows no price comparison. Use the official links in the table.
GPT-6.1 Terra has the larger context window: 1.05M tokens against 1M tokens.
Same output limit: up to 128K tokens per request.

Measure	GPT-6.1 Terra	Claude Sonnet 5.5
Provider	OpenAI	Anthropic
API price	Not confirmed right now. Check the official page	$2 in / $10 outCached input $0.1per 1M tokens, USD
Context window	1.05M tokens	1M tokens
Max output	128K tokens	128K tokens
Availability	Generally available	Available (listed as current in official docs)
Retirement	None listed in Kingy AI Deadlines	None listed in Kingy AI Deadlines
Price check	Human-reviewedChecked Nov 12, 19:43 UTC	Human-reviewedChecked Nov 13, 01:10 UTC
Official sources	developers.openai.com › gpt-6.1-terra developers.openai.com › pricing developers.openai.com › prompt-caching	platform.claude.com › pricing platform.claude.com › overview platform.claude.com › prompt-caching

Larger is not always better: a bigger context window or output limit only matters if your work needs it. These figures compare price and limits, not answer quality.

What common workloads cost

At 10,000 requests a month, standard list rates. Change the numbers in the tool below for your own usage.

Measure	GPT-6.1 Terra	Claude Sonnet 5.5
Chat reply2,000 in / 500 out	Price not confirmed right now	$90.00 a month$0.009 per request
Coding agent step30,000 in / 2,000 out	Price not confirmed right now	$800 a month$0.08 per request
Long document summary150,000 in / 1,500 out	Price not confirmed right now	$3,150 a month$0.32 per request
Classify short text300 in / 20 out	Price not confirmed right now	$8.00 a month$0.0008 per request

Excludes prompt-cache discounts, batch and priority pricing, regional rates, tool fees and tax. Reasoning tokens count as output, so a model that thinks longer costs more per request than these figures show.

What Kingy measured

Kingy's own runs, not vendor claims. These are small tests: read each one for its tasks and limits before generalising. All results are also on the AI Model Board.

Test	GPT-6.1 Terra	Claude Sonnet 5.5
AI Accuracy Index: 125 official figures from memory, 2 asks each	Right 59%, wrong 6.0%, not sure 35%2026-11-10 · read the test	Right 62%, wrong 10.4%, not sure 28%2026-11-10 · read the test
Kingy's four coding and data tasks, 5 tries each	20/20 passed · Kingy's bill $0.025912026-11-09 · read the test	20/20 passed · Kingy's bill $0.086342026-11-09 · read the test

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What would it cost you?

Input tokens per request Output tokens per request Requests per month

Standard list rates only. Excludes prompt-cache discounts, batch and priority pricing, regional rates, tool fees and tax. Reasoning tokens count as output. A long-context rate applies when one request's input passes the model's threshold.

Prices of other AI models

See the checked prices of all the main AI models in one table, or pick any two models in the tool above.

How this works

Prices come from the same checked data behind Kingy's AI cost calculator and the Kingy Facts API. OpenAI, Anthropic and Google prices are reviewed by a person and re-checked against the official pricing page every few hours. Prices for other providers are read automatically from their official pricing pages by fixed rules, and the table says so.

"Not confirmed right now" means Kingy could not confirm the price within its check window, so it shows no number. Use the official link instead. Retirement dates come from Kingy AI Deadlines. Every source re-check is logged in the public accuracy ledger.

Why isn't my model listed?

Only models with a tracked official price page are listed. Embedding, rerank and moderation models are left out because they have no output price to compare.

Does this show benchmarks?

It shows Kingy's own tests when a model has been through them: the AI Accuracy Index and Kingy's coding and data tasks. These are small tests, so read each one for its tasks and limits before generalising. Vendor benchmarks are left out, because results depend on the test and settings used; Kingy's full comparisons cover them when one exists for your pair.