What Is GPT-6.1? Sol vs Terra Explained (2026 Pricing & Access)

What Is GPT-6.1? Sol vs Terra Explained (2026 Pricing, Access & Content Rules)

If you've seen "GPT-6.1" in your feed this week and assumed it's one new ChatGPT model, you're not alone. It isn't. GPT-6.1 is a family, and so far it has two members: GPT-6.1 Sol, released on September 29, 2026, and GPT-6.1 Terra, released on October 26, 2026.

Neither one is in regular ChatGPT Chat. Both are built for agent-style work: coding, computer use and documents. This guide covers what each model is, what it costs, where you can actually use it, and what OpenAI's rules mean for anyone hoping for a looser model.

TL;DR

GPT-6.1 Sol (Sep 29, 2026): an upgrade to GPT-6 Sol that OpenAI says "nearly matches GPT-6 Astra" on agentic coding, computer use and professional work, at one-fifth of Astra's API price. API: gpt-6.1-sol, $2 / $10 per million input/output tokens.
GPT-6.1 Terra (Oct 26, 2026): a faster, cheaper mid-tier model for visual reasoning, precise computer use and "clearer, more natural writing." API: gpt-6.1-terra, $1 / $5 per million tokens, with a 1,050,000-token context window.
There is no GPT-6.1 Astra. OpenAI didn't ship one (TechCrunch).
Where to use it: ChatGPT Work and Codex on paid plans, the OpenAI API, and OpenRouter. Not in ChatGPT Chat.
Content rules: both models use the same safeguards stack as GPT-6 Astra. ChatGPT's "adult mode" is still shelved. If you want NSFW chat, see Can GPT-6.1 Do NSFW?, or go straight to an uncensored platform like HackAIGC.

GPT-6.1 at a Glance

	GPT-6.1 Sol	GPT-6.1 Terra
Released	Sep 29, 2026 (OpenAI DevDay)	Oct 26, 2026
Positioning	Near-Astra intelligence for coding, computer use and professional work	Fast, efficient model for visual reasoning, computer use and writing
API model ID	`gpt-6.1-sol`	`gpt-6.1-terra`
Standard API price (input / cached / output per 1M tokens)	$2 / $0.10 / $10 (prompts up to 272K tokens)	$1 / $0.05 / $5
In ChatGPT	Work + Codex (Plus, Pro, Business, Enterprise, Edu)	Work + Codex (Plus, Pro, Enterprise, Edu)
In ChatGPT Chat	No	No
On OpenRouter	Yes	Yes

Sources: Introducing GPT-6.1 Sol, Introducing GPT-6.1 Terra, OpenAI API changelog, GPT-6.1 Terra model page.

Where GPT-6.1 Fits in OpenAI's Lineup

OpenAI now names its models in tiers, not just version numbers. Within the GPT-6 generation:

Astra is the flagship (GPT-6 Astra).
Sol is the cost-efficient high-end tier (GPT-6 Sol, then GPT-6.1 Sol).
Terra is the balanced mid-tier (GPT-6.1 Terra replaces GPT-5.6 Terra).
Luna is the fast, cheapest tier (GPT-6 Luna).

So "GPT-6.1" doesn't mean "smarter than GPT-6 Astra." OpenAI describes GPT-6.1 Sol as nearly matching Astra at a lower price. It describes Terra as a big step up from GPT-5.6 Terra. If you need a refresher on how the tiers started, our GPT-5.6 Sol, Terra and Luna explainer covers the previous generation.

GPT-6.1 Sol: What's New

According to OpenAI's announcement, GPT-6.1 Sol is "an upgrade to GPT-6 Sol that nearly matches GPT-6 Astra's intelligence on agentic coding, computer use, and professional work at one-fifth of Astra's standard input and output token prices."

Key points:

Launched at DevDay, a week after GPT-6 Sol (TechCrunch).
Cheaper cached input: $0.10 per million cached tokens. OpenAI says that's 95% less than its standard input price and 50% less than GPT-6 Sol's cached rate.
Multi-agent (beta) in the Responses API: the model can hand work off to subagents (changelog).
Sol Ultrafast was announced for Codex, with "up to 8x faster token generation."
No GPT-6.1 Astra. TechCrunch reported that OpenAI skipped the expected 6.1 Astra. Citing the Wall Street Journal, it said internal testing showed more deception and a tendency to go ahead with tasks without asking permission.

GPT-6.1 Terra: What's New

OpenAI's Terra announcement describes it as "a fast, efficient model that combines detailed visual reasoning and precise computer use alongside clearer, more natural writing." OpenAI's own claims:

Price: standard API prices are "50% lower than those of GPT-5.6 Terra and GPT-6.1 Sol."
Computer use: at medium reasoning effort, it scores 15 points higher than GPT-5.6 Terra on OpenAI's Agents' Last Exam benchmark "at about one-third the cost." OpenAI also says it performs "on par with GPT-6 Astra at only one-tenth its price per token."
Speed: OpenAI says it completes tasks "over three times faster than both GPT-6 Astra and GPT-6.1 Sol."
Factuality: on OpenAI's internal set of error-inducing prompts, the low-effort error rate dropped from 53.6% (GPT-5.6 Terra) to 16.7%.
Coding: 50.3% on Terminal-Bench 4.0 at max effort. OpenAI still recommends GPT-6.1 Sol and GPT-6 Astra "for the most complex coding tasks."

The developer model page lists the specs:

Context: 1,050,000 tokens (922,000 max input, 128,000 max output)
Inputs / outputs: text and image in, text out. No audio or video.
Knowledge cutoff: June 1, 2026
Reasoning effort: none, low, medium (default), high, xhigh, max
Tool calling: requires the Responses API

OpenRouter lists Terra at $1 / $5 per million tokens through OpenAI. It also lists a cheaper Flex endpoint ($0.50 / $2.50) and a pricier Fast endpoint ($2 / $10), plus a "Terra Pro" variant that runs the same model in pro reasoning mode.

Sol vs Terra: Which One Is "Better"?

It depends on the job:

Pick Sol for long, complex coding or multi-step professional work, where OpenAI positions it closest to Astra.
Pick Terra for high-volume work, screenshots and on-screen content, form-filling-style computer use, and everyday writing. It costs half as much and OpenAI says it's faster.

Both share one important trait: neither is designed to be a looser model. That matters if you're here because you want fewer refusals.

Where Can You Use GPT-6.1?

ChatGPT Work and Codex: both models are available on paid plans. The OpenAI Help Center says GPT-6.1 Terra "is not available in Chat," and lists GPT-6.1 Sol as an option for Work and Codex only.
ChatGPT Chat: when you pick GPT-6 in Chat, GPT-6 Sol powers Instant through Extra High, and GPT-6 Astra powers Pro. Free and Go users get GPT-5.6 Luna. GPT-6.1 isn't in the Chat model menu.
OpenAI API: gpt-6.1-sol and gpt-6.1-terra. API usage is billed separately from ChatGPT subscriptions (release notes).
OpenRouter: both are listed. OpenRouter notes Terra isn't currently available through EU in-region routing.

GPT-6.1 Content Rules: What It Won't Do

This is where many of our readers get disappointed.

Same safeguards as Astra. OpenAI's system card addendum for Terra says it "uses the same safeguards stack as GPT-6.1 Sol and GPT-6 Astra." OpenAI treats it as Critical in cybersecurity and High for biological and chemical capability.
Usage Policies apply. The system card points to OpenAI's Usage Policies, which apply to all OpenAI services.
Erotic content: for image inputs, the system card reports that Terra performs "on par with GPT-5.6 Terra for self-harm and harms-erotic." It also says Terra improved on teen-specific (U18) safety evaluations, including disallowed sexual content.
Jailbreak resistance: Terra "performs on par with GPT-5.6 Terra" against adaptive multi-turn jailbreak attempts, per the system card.
No adult mode. OpenAI delayed ChatGPT's planned "adult mode" in March 2026 (Axios), then reportedly shelved it "indefinitely" (Reuters). GPT-6.1 didn't change that. More in ChatGPT Adult Mode Shelved: Alternatives.

Writers have also noticed that GPT-6.1 tones down romance, violence and explicit scenes. We compare that with GPT-5.6 Sol in GPT-6.1 vs GPT-5.6 Sol for NSFW & Creative Writing.

What Early Users Are Saying

Terra is only a day old, so most feedback so far is about GPT-6.1 Sol. In an r/OpenAI thread, users called it very capable and cheap to run, and good at computer and browser use. They also called it "a bit boring" and slow on long tasks. On r/WritingWithAI, writers complained that its choppy, "staccato" prose wasn't fixed in 6.1. These are individual opinions, not benchmarks, but they're consistent.

If You Want an Uncensored Option

GPT-6.1 is a strong work model. It is not, and isn't trying to be, an uncensored one. If what you actually want is adult roleplay, explicit fiction, or blunt answers without a lecture, you have three routes:

Jailbreak it. Possible in theory, fragile in practice. See How to Jailbreak GPT-6.1 for a prompt, its limits and the risks.
Fall back to an older OpenAI model. Some writers prefer GPT-5.6 Sol (see our comparison above).
Use a platform built for it. HackAIGC offers uncensored AI chat, plus an uncensored image generator and video generator, with no prompt hacks. It keeps hard limits like no minors and no real-person targeting.

FAQ

What is GPT-6.1?

GPT-6.1 is OpenAI's latest model family in the GPT-6 series. It includes GPT-6.1 Sol (Sep 29, 2026) and GPT-6.1 Terra (Oct 26, 2026). There's no GPT-6.1 Astra.

What's the difference between GPT-6.1 Sol and GPT-6.1 Terra?

Sol is the higher-end model for complex coding and professional work at $2 / $10 per million tokens. Terra is faster and costs half as much ($1 / $5). OpenAI aims it at visual reasoning, computer use and everyday writing.

Is GPT-6.1 available in ChatGPT?

Only in ChatGPT Work and Codex on paid plans. OpenAI's help center says GPT-6.1 Terra is not available in Chat, and Sol is listed for Work and Codex only.

How much does GPT-6.1 Terra cost?

$1 per million input tokens, $0.05 per million cached input tokens, and $5 per million output tokens on the standard API. OpenRouter also lists Flex and Fast endpoints at different prices.

Can GPT-6.1 generate NSFW content?

It runs under OpenAI's Usage Policies and the same safeguards as GPT-6 Astra, and ChatGPT's adult mode is still shelved. Full breakdown: Can GPT-6.1 Do NSFW?

Is GPT-6.1 on OpenRouter?

Yes. OpenRouter lists both GPT-6.1 Terra and GPT-6.1 Sol, along with Pro variants.

Conclusion

GPT-6.1 is OpenAI making agent-grade AI cheaper and faster. Sol comes close to Astra at a fifth of its price, and Terra does solid work for half of that. Both are work models living in Work, Codex and the API, and both inherit OpenAI's full safety stack.

If you came looking for a model that writes what you ask without the hedging, GPT-6.1 isn't it. Try HackAIGC's uncensored chat instead.

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