AI models in October 2026: who leads, what it costs, what to choose

The closed labs and their flagships

Who sells what, since when and at what list price.

Anthropic. Claude Fable 5.1 is its most capable widely released model; its twin, Mythos 5.1, is limited to a small set of vetted organizations. Anthropic's docs still recommend starting with Opus 5.5 for most workloads (details in our Opus 5.5 analysis). With Sonnet 5.5 and Haiku 5.5 out, Sonnet 5 and Haiku 4.5 are now legacy models, still available, and Sonnet 4.5 retires on November 30, 2026.

OpenAI. GPT-6 Astra (see our analysis) is its first model rated "Critical" for cybersecurity under its Preparedness Framework, so the public version refuses advanced offensive tasks. GPT-6 Sol and Luna launched at half the promotional price of their GPT-5.6 predecessors; OpenAI shut down o1 and o4-mini on October 23, 2026 and will shut down o3 and o3-pro on December 11. On September 29 it launched GPT-6.1 Sol, which it says nearly matches Astra on agentic coding, computer use and professional work at one fifth of the price, and which has taken GPT-6 Sol's place in its flagship list at the same price; on October 26 it added GPT-6.1 Terra ($1/$5), built for computer use.

Google. On September 30 it announced Gemini 4 Argon, its new flagship, at first only for trusted defenders in its Fairwind Program; since October 13 it has been generally available in the API, at $2/$10 until November 30 and $4/$20 from December 1. Gemini 3.5 Pro, expected in June, is still missing: Bloomberg reported on July 16 that its coding performance fell short. Meanwhile a new Flash model shipped almost every month (3.5 in May, 3.6 in July, 3.7 in August, 3.8 in September), and Gemini 3.1 Pro is still in preview.

SpaceXAI. SpaceX absorbed xAI in February 2026, renamed it in July and bought the code editor Cursor in August. Grok 4.7 has slipped from sixth to tenth on the official Terminal-Bench 4.0 board (37.6%).

Meta, Microsoft, Amazon. Muse Spark (April 8) was Meta's first model without open weights; on October 12 came Muse Wonder (API, $4/$20) and Muse Wonder Full (Muse Code only), which scores 50 on the Artificial Analysis index v5.0. Microsoft unveiled MAI-Thinking-1, its first reasoning model, in June (price unconfirmed). Amazon moved Nova Premier and other Nova models to maintenance mode, according to Business Insider (via eWeek).

Open weights in brief

Open-weight models have grown huge (Kimi K3 has 2.8 trillion parameters, 104 billion active per token) but still trail the closed leaders: the best, DeepSeek V4.1-Flash and Z.ai's GLM-5.3, score 32 on the Artificial Analysis index v5.0 against 58 for Claude Opus 5.5.

Mistral unveiled Mistral Large 4, a 1-trillion-parameter model, on October 6, for now API-only (Artificial Analysis gives its preview 25 points on index v5.0); it plans to release the weights about three weeks later.

DeepSeek V4.1-Flash (MIT license) is the cheapest near-frontier API we found, at $0.30/$1.20 at peak hours and half that off-peak, and licenses are drifting toward custom terms with revenue thresholds. More in our open-weight guide.

Price bands: four tiers, not one market

The list price tells you the band; your cost per task tells you the bill.

The $10/$50 tier is a 2026 novelty (Claude Fable 5 in June, then Fable 5.1 and GPT-6 Astra), while the middle got cheaper: GPT-6 Sol costs half its predecessor's promotional price, Opus 5.5 is 20% cheaper per token than Opus 5, and Sonnet 5 kept $2/$10 instead of rising to $3/$15.

Three details move a real bill more than the list price: long prompts (above 272K input tokens OpenAI bills the whole request at twice the input and cache rates and 1.5 times the output rate; Claude has no surcharge except on Haiku 5.5 above 100K tokens), cache reads (5% of the input price on Opus 5.5, Sonnet 5.5, GPT-6.1 Sol and Gemini 4 Argon, 10% on GPT-6) and scheduled rises (Gemini 3.6 Flash and 3.8 Flash double on January 1, 2027). Method in our AI cost guide. To learn how we put these models to work in each business, explore our AI for companies services.

Leaderboards: what they measure, who leads

Each ranking answers a narrower question than "which model is best".

Vendor tables are run or chosen by the lab itself, usually at its highest effort and on benchmark versions a few weeks old. Independent boards apply one method to everyone but lag behind and give different numbers: Anthropic's reported 66.4% for Opus 5.5 on Terminal-Bench 4.0 was not yet on the official board on September 26, which showed 64.8% on October 8 and still did on October 27.

Versions also break comparisons: OpenAI's Astra post quotes Artificial Analysis index v4.1.1 values of up to 65.7, while v5.0, which replaced v4.3.2 in late October and is not comparable with it, tops out at 58, a new scale rather than weaker models. Arena, for its part, ranks by human preference votes, not by tasks completed.

None of these tests uses business Spanish or French: they filter a shortlist, they don't decide it. Our method is in the evals guide.

How to choose by use case

A shortlist to test, not a verdict.

Include a second vendor and an open-weight option in every shortlist. Our method (30 fixed prompts per client, five engines per run, three languages) is described in how we choose models.

Seven verified trends of 2026

• A premium tier, yet cheaper capability. On ARC-AGI-2, a score of about 61 to 65% cost $2.25 per task with Claude Opus 4.6 in February and $0.042 with DeepSeek V4 Flash in July.
• Reasoning effort is a setting. Claude, GPT-5.6, GPT-6 and Gemini 3.x expose effort levels; on ARC-AGI-2 on September 26, Opus 5.5 cost $0.241 per task at low effort and $1.85 at max (see our reasoning guide).
• 1M tokens of context is the norm for flagships; Grok 4.7 stops at 500K.
• Offensive cyber capability is gated. Mythos 5.1 is limited to a small set of vetted organizations, Gemini 3.8 Flash Cyber and Gemini 4 Argon without cyber guardrails to trusted defenders in Google's Fairwind Program, and OpenAI plans wider defensive access to Astra through its Daybreak program.
• Products disappear quickly. OpenAI closed the Sora app in April, about seven months after launch, removed the Sora 2 API on September 24 and shut its Atlas browser on August 9; Nova Premier reached end of life on September 14.
• US policy can cut access. A US export-control directive made Anthropic pull Fable 5 and Mythos 5 for all users on June 12 (Fable 5 returned on July 1), and Executive Order 14409 (June 2) calls for a voluntary framework giving the government up to 30 days of pre-release access to "covered frontier models". Since September 29 Washington has added a voluntary pledge by six AI companies (White House Accord on Super Intelligence), an executive order on "super intelligence", an FTC probe into rogue AI agents and a "Super Intelligence Force" (October 4).
• Labs debate a slower pace. In We Must Pace the Frontier, Dario Amodei called for slowing capability gains and committed Anthropic to embedded third-party evaluators; Sam Altman matched that commitment on September 14. One trigger he cites: the July incident in which OpenAI agents under evaluation reached Hugging Face systems (OpenAI's report). On September 28 OpenAI dropped GPT-6.1 Astra, saying it fell short on scope, authorization and reporting back to the user.

What it means for companies in Colombia, Latin America and Europe

Keep a tested fallback. The Fable 5 withdrawal lasted 19 days and hit every customer. A production system in Bogotá, Mexico City or Paris needs a second model from another vendor, tested on the same prompts, and an open-weight option you could host.

Budget for residency. OpenAI adds 10% for regional processing on models released since March 5, 2026; Claude costs 10% more on regional Bedrock or Google Cloud endpoints.

Put retirement dates in contracts. Anthropic commits to Opus 5.5 until at least September 22, 2027; Haiku 4.5, now legacy, has passed October 15, 2026, its guaranteed minimum date, and remains available with no retirement date yet (Anthropic promises at least 60 days' notice), while Sonnet 4.5 retires on November 30. Ask every vendor for such dates, notice periods and a migration clause.

Test Spanish and French yourself. At Slash AI Lab every candidate goes through 30 fixed prompts per client in Spanish, English and French before deployment; no leaderboard replaces that step.

Building from the US? Our Bogotá team runs these evaluations and builds the integration on US business hours: see nearshore software development in Colombia.

Check the reach of the EU AI Act. Article 2(1)(c) covers providers and deployers outside the EU when their system's output is used in the EU, so a Colombian firm serving French clients can be in scope. In Colombia, check how Law 1581 of 2012 applies before sending personal data abroad. More in our 2026 regulatory map.