All three launched new flagships in the past month, and all three say theirs is the best. We checked the independent leaderboards, the prices and the privacy settings — and the answer depends on what you need.
Evidence review of independent leaderboards, official pricing and privacy pages, checked 14–15 Oct 2026. Disclosure: research for this page was assisted by AI tools, including Claude, made by one of the companies compared — so every figure here links to an independent or official source you can check. Hyptor Lab’s blind 25-task test is scheduled. No affiliate links. How we test
The short answer
There’s no single winner. Gemini 4 Argon tops the biggest human-preference leaderboard; Claude Opus 5.5 leads two independent capability indexes; OpenAI’s best models trail on both. All three cost about $20 a month.
Base price: ~$20/month for all three · Cheapest paid: Google AI Plus $4.99 · Privacy: check the training setting on whichever you use · Confidence: Medium — rankings change weekly and overlap heavily at the top.
What they claim vs what independent rankings show
| Their claim | Verdict | What the evidence shows |
|---|---|---|
| OpenAI: GPT-6 Astra is “the most intelligent and aligned model in the world” [9] | Overstated | Independent indexes put it level with or behind rivals: tied 3rd on the Artificial Analysis index (53 vs Claude Opus 5.5’s 58) [11]; best OpenAI model 22nd on LMArena [10]. |
| Anthropic: Opus 5.5 is “our strongest model on most measures of honesty” [5] | Holds, with caveats | It scores highest on AA-Omniscience, which penalises wrong answers (46 vs GPT-6 Astra’s 44) [13] — but Gemini 4 Argon has no score there yet. |
| Google: Argon is “ranking #1 on the Vals Index” [7] | Untested | We didn’t verify the Vals Index. Argon is #1 on LMArena’s text leaderboard [10], though the top ranks overlap within error margins. |
| OpenAI: GPT-6 Sol “makes about half as many mistakes as its predecessor” [9] | Holds, with caveats | Measured on internal conversations OpenAI says “are not representative of typical usage” [9]. Vectara’s summarisation test: 6.5% hallucination rate for GPT-6 Sol vs 12.4% for GPT-5.6 Sol [16]. |
Why this matters
Millions of people pay around $20 a month for one of these assistants. Launch posts are written to impress; independent leaderboards are where claims meet competition. A confident wrong answer costs you more than a slow right one, so factuality matters as much as raw intelligence.
How we built this verdict
We compared three independent sources — LMArena’s human-preference leaderboard [10], the Artificial Analysis Intelligence Index [11] and Epoch AI’s Capabilities Index [12] — plus two factuality benchmarks [13][16], each vendor’s pricing page [3][4][6] and privacy documentation [21–24]. Leaderboards were viewed 14–15 Oct 2026 and change often.
Gemini 4 Argon wins the popularity vote
Finding: on LMArena’s text leaderboard (8.8 million votes, updated 13 Oct), Gemini 4 Argon ranks #1 (1525), Claude Opus 5.5 #3 (1508) and the best OpenAI model, GPT-6.1 Sol, #22 (1484) [10]. The top ten’s confidence ranges overlap heavily.
In practice: people comparing answers side by side currently prefer Argon slightly — but the gap between the top few is within the margin of error.
Claude Opus 5.5 leads the capability indexes
Finding: Artificial Analysis scores Claude Opus 5.5 at 58, with GPT-6 Astra and Gemini 4 Argon tied at 53 [11]. Epoch AI puts Opus 5.5 at 167 and GPT-6 Astra at 166 — effectively a tie — and hasn’t listed Argon yet [12].
In practice: on demanding reasoning and coding tasks, Claude and OpenAI’s top models are close; Gemini’s newest model is too new for some indexes.
The surprise: OpenAI halved its hallucination rate
On Vectara’s summarisation hallucination test, GPT-6 Sol’s rate (6.5%) is about half that of its predecessor (12.4%) [16] — consistent with OpenAI’s own claim. The catch: Vectara hasn’t yet tested Claude 5.x or Gemini 4, so it can’t tell you which of today’s flagships hallucinates least.
Where each one genuinely shines
Gemini: top human-preference ranking [10], a $4.99 entry tier and 5 TB of storage with AI Pro [6]. Claude: highest independent capability and factuality scores this month [11][13]. ChatGPT: unlimited text chats on the free plan (subject to abuse limits) and the broadest range of plans [3].
What they really cost
| Tier | ChatGPT | Claude | Gemini |
|---|---|---|---|
| Free | GPT-6, unlimited text chats* | Sonnet & Haiku | Flash-Lite |
| Entry paid | Go (price not shown on page) | — | AI Plus $4.99 |
| Standard | Plus $20 | Pro $20 ($17 annual) | AI Pro $19.99 |
| Power | Pro $100 / $200 / $500 | Max $100 / $200 | Ultra $99.99 / $199.99 |
Privacy: who trains on your chats by default?
ChatGPT: content “is used to train our models” on Free, Go, Plus and Pro, with an opt-out [3][21]. Gemini: trains on your activity while Keep Activity is on, with human reviewers; activity auto-deletes after 18 months, and chats are kept 72 hours even when it’s off [24]. Claude: uses chats for training only if you “choose to allow” it, keeping that data up to 5 years if you do [22][23] — check your own setting, as we couldn’t confirm the default.
Which one should you use?
On a budget: start with all three free tiers; Google AI Plus is the cheapest upgrade. Heavy writing, research or coding: Claude and ChatGPT’s top tiers lead the capability indexes. Google Workspace users: Gemini’s storage and integration may decide it. Privacy-sensitive: turn off training wherever it’s on, and avoid entering confidential information — Google says so too [24].
Questions people ask
Which is better: ChatGPT, Claude or Gemini?
It depends on the measure. Gemini leads LMArena [10]; Claude leads Artificial Analysis and Epoch [11][12]. Differences at the top are small.
Which one makes the fewest mistakes?
On AA-Omniscience, Claude Opus 5.5 scores highest (46), then GPT-6 Astra (44) [13]. Gemini 4 Argon hasn’t been scored yet.
Is it worth paying for more than one?
For most people, no. The free tiers are good enough to find the one whose style suits you before paying $20 for it.
The verdict
“The best AI” changes month to month, and this month the honest answer is a near three-way tie with different strengths. The decision: try all three free tiers on your own real tasks, then pay for the one you reach for most — and switch off training if privacy matters to you.
Change log
15 Oct 2026 — Published as an evidence review (leaderboards viewed 14–15 Oct). Re-check scheduled for January 2027.
Sources
- OpenAI, ChatGPT release notes — help.openai.com
- OpenAI Help, “GPT-6 and other models in ChatGPT” — help.openai.com
- OpenAI, ChatGPT pricing — chatgpt.com
- Anthropic, Claude pricing — claude.com
- Anthropic, “Introducing Claude Opus 5.5”, 22 Sep 2026 — anthropic.com
- Google, Gemini subscriptions (US) — gemini.google
- Google, “Gemini 4 Argon: Built to solve your hardest problems”, 13 Oct 2026 — blog.google
- Google, “Gemini 4 Argon comes to the Gemini app”, 13 Oct 2026 — blog.google
- OpenAI, “Introducing GPT-6 Sol and Luna” — openai.com
- LMArena text leaderboard, updated 13 Oct 2026 — lmarena.ai
- Artificial Analysis, LLM leaderboard — artificialanalysis.ai
- Epoch AI, Epoch Capabilities Index — epoch.ai
- Artificial Analysis, AA-Omniscience — artificialanalysis.ai
- OpenAI Help, “What is ChatGPT Plus?” — help.openai.com
- OpenAI Help, “About ChatGPT Pro tiers” — help.openai.com
- Vectara hallucination leaderboard, updated 22 Sep 2026 — github.com
- Florida Attorney General press release, 1 Jun 2026 (allegations) — myfloridalegal.com
- BleepingComputer, Claude outage, 3 Sep 2026 — bleepingcomputer.com
- MediaPost, usage-limits lawsuit (allegations), 17 Jun 2026 — mediapost.com
- heise online, Gemini outage, 10 Jun 2026 — heise.de
- OpenAI Help, “Data controls in ChatGPT” — help.openai.com
- Anthropic Privacy Center, “Is my data used for model training?” — privacy.claude.com
- Anthropic Privacy Center, “How long do you store my data?” — privacy.claude.com
- Google, Gemini Apps Privacy Hub, updated 13 Oct 2026 — support.google.com
Reliability notes
Documented incidents in 2026 include outages for Claude [18] and Gemini [20], a lawsuit by Florida’s Attorney General against OpenAI [17] and a class action over Claude Max usage limits [19]. Lawsuits are allegations, not findings. Vendors can respond via our contact page.