GPT-6.1 Terra: Price, Benchmarks, API & vs Sol/Astra (Oct 2026)

GPT-6.1 Terra launched Oct 26, 2026: $1/$5 per 1M tokens, 1.05M context, 60% on Agents' Last Exam. API id, benchmarks and how it compares to Sol and Astra.

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Quick answers

What is GPT-6.1 Terra?
OpenAI's fast, low-cost model in the GPT-6 family, released Oct 26, 2026. It is built for computer use, visual reasoning and clear writing, and replaces GPT-5.6 Terra.
How much does GPT-6.1 Terra cost?
$1 per 1M input tokens and $5 per 1M output tokens in the API, with cached input at $0.05. Batch and Flex are 50% off. That is half of GPT-6.1 Sol and one-tenth of GPT-6 Astra.
Is GPT-6.1 Terra in the API?
Yes, as gpt-6.1-terra. It takes text and image input, has a 1.05M-token context window and up to 128K output tokens.
Who can use GPT-6.1 Terra in ChatGPT?
Plus, Pro, Enterprise and Edu users, in ChatGPT Work and Codex.
Is GPT-6.1 Terra better than Sol or Astra?
Close on vision and computer use, and over 3x faster, but behind on hard coding. OpenAI recommends Sol or Astra for deep research and complex coding.
GPT-6.1 Terra spec card: $1/$5 per 1M tokens, 1.05M context, 128K output, benchmark scores and API price vs GPT-6.1 Sol, Claude Opus 5.5 and GPT-6 Astra

OpenAI released GPT-6.1 Terra on October 26, 2026, almost a month after GPT-6.1 Sol. It is the mid-priced model of the lineup: smarter than GPT-6 Luna, cheaper and faster than Sol and Astra, and tuned for the screen-and-document work that fills a workday.

1. GPT-6.1 Terra at a glance

Spec

GPT-6.1 Terra

Release date

Oct 26, 2026

API model id

gpt-6.1-terra

Input / output

Text and image in, text out

Context window

1,050,000 tokens

Max output

128,000 tokens

Knowledge cutoff

Jun 1, 2026

Reasoning effort

none to max (default medium)

Input price

$1.00 / 1M tokens

Cached input

$0.05 / 1M tokens

Output price

$5.00 / 1M tokens

Batch / Flex

50% off

Fast mode

2x standard

Long prompts (>272K input)

2x input, 1.5x output

ChatGPT access

Plus, Pro, Enterprise, Edu (ChatGPT Work, Codex)

GPT-6.1 Terra specs and pricing, Oct 27, 2026 · OpenAI GPT-6.1 Terra model page · Accessed

2. GPT-6.1 Terra price

GPT-6.1 Terra price is the main story. At $1 in and $5 out per million tokens, it costs 50% less than GPT-5.6 Terra and GPT-6.1 Sol, and 10x less than GPT-6 Astra.

Model

Input / 1M

Output / 1M

GPT-6.1 Terra

$1

$5

GPT-6.1 Sol

$2

$10

Claude Sonnet 5.5

$2

$10

Claude Opus 5.5

$4

$20

GPT-6 Astra

$10

$50

Per task, the gap is bigger. On Agents' Last Exam at medium effort, Terra costs $0.29 per task versus $0.84 for GPT-5.6 Terra and $4.82 for GPT-6 Astra. In ChatGPT Work and Codex, your usage allowance also lasts longer on Terra than on Sol or Astra.

3. GPT-6.1 Terra benchmarks

Scores from OpenAI's launch charts, at max reasoning effort unless noted:

Benchmark

GPT-6.1 Terra

GPT-6.1 Sol

GPT-6 Astra

Claude

Agents' Last Exam v1

60.0% ($1.01/task)

58.6%

59.3% ($7.24/task)

Opus 5.5: 63.2% ($8.82/task)

Agents' Last Exam v1 (medium)

57.6% ($0.29/task)

-

57.6% ($4.82/task)

-

MMMU-Pro (Vision)

85.5%

86.3%

86.7%

-

OSWorld 2.1 offline

74.2%

78.0%

80.9%

Sonnet 5.5: 83.9%

Terminal-Bench 4.0

50.3%

55.9%

58.2%

Sonnet 5.5: 70.6%

Terminal-Bench-Science 0.1

58.3%

57.0%

68.1%

Opus 5.5: 63.3%

  • Computer use: Terra beats Sol and Astra on Agents' Last Exam at a fraction of the cost and finishes tasks over 3x faster on average.
  • Vision: within about 1 point of Sol and Astra on MMMU-Pro.
  • Factuality: on OpenAI's error-inducing prompt set, the low-effort error rate fell from 53.6% (GPT-5.6 Terra) to 16.7%; at max effort it fell to 4.3%.
  • Coding: Terminal-Bench 4.0 more than doubled from 21.5%, but Terra still trails Sol, Astra and Claude Sonnet 5.5.
  • Third party: on DualEntry's accounting benchmark Terra scored 78.2% (18th of 22) but was the fastest OpenAI model at 16.1 seconds per task.

4. GPT-6.1 Terra API

The GPT-6.1 Terra API id is gpt-6.1-terra. Tool calling runs through the Responses API, with computer use, hosted shell, code interpreter, web search, file search and MCP. Set reasoning effort from none to max; medium is the default. Good fits, per OpenAI: filling out forms, matching product photos to catalog entries, interpreting technical drawings, drafting proposals and editing videos.

Safety note: OpenAI's system card addendum treats Terra as Critical capability in cybersecurity, the same as GPT-6 Astra, so the same safeguards apply.

5. GPT-6.1 Terra vs. Sol vs. Astra: which to use

  • GPT-6.1 Terra: high-volume agent work, screens, forms, documents, writing. Best price per task.
  • GPT-6.1 Sol: harder reasoning and coding, at 2x Terra's price.
  • GPT-6 Astra: the top model for deep research and the hardest coding, at 10x.
  • GPT-6 Luna: cheapest, about one-tenth of Terra, for simple tasks.

6. Use GPT-6.1 Terra with your team

Yes, you can use GPT-6.1 Terra side by side with other top models in Sumus. Sumus is a group chat where AI employees work next to your team, and you can switch models per task: Terra for fast, cheap screen and document work, a heavier model when the job needs it. One thread, every model, no separate subscriptions.

FAQ

When was GPT-6.1 Terra released?

October 26, 2026, in ChatGPT Work, Codex and the OpenAI API.

What is the GPT-6.1 Terra price?

$1 per 1M input tokens, $0.05 cached input and $5 per 1M output tokens. Batch and Flex are 50% off; prompts over 272K tokens cost more.

What is the GPT-6.1 Terra context window?

1.05M tokens, with up to 128K output tokens.

Is GPT-6.1 Terra free?

Not on the free ChatGPT plan; it is for Plus, Pro, Enterprise and Edu users. In the API it is paid per token.

GPT-6.1 Terra vs GPT-5.6 Terra?

Terra 6.1 is cheaper (half price) and much stronger: 57.6% vs 42.6% on Agents' Last Exam at medium effort, and 50.3% vs 21.5% on Terminal-Bench 4.0.

Is GPT-6.1 Terra good for coding?

For everyday coding, yes. For complex coding, OpenAI recommends GPT-6.1 Sol or GPT-6 Astra; Claude Sonnet 5.5 also scores higher on Terminal-Bench 4.0.

Sources

Update log

  • — Oct 27: First published. GPT-6.1 Terra released Oct 26, 2026; specs, price and benchmarks from OpenAI.
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This page was written by a Sumus AI Employee

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