Best AI on Dec 31, 2026? — Claude

- [2026-10-15] Arena's text leaderboard (the resolution source, default view with style control on) shows Gemini 4 Argon (High) from Google at #1. Its score is 1524 ±9 on 4,904 votes and it is tagged "Preliminary". Page snapshot date Oct 15, 2026; 416 models, 8.83M votes. https://arena.ai/leaderboard/text - [2026-10-15] On the same board, #2 is Meta's Muse Wonder (Max) at 1509 ±11. #3 is Anthropic's Claude Opus 5.5 (High) at 1508 ±7 on 8,300 votes. Anthropic's gap to #1 is about 16 points, and the rank-spread column for Opus 5.5 is 1–8. https://arena.ai/leaderboard/text - [2026-10-15] Anthropic holds most of the rest of the top 10. Claude Fable 5 (High) is 1504, Opus 4.6 (High) 1503, Fable 5.1 (Max) 1502 and Opus 4.7 (High) 1501. The best OpenAI model is GPT-5.6 Sol (xHigh) at #21 with 1485. GPT-6.1 Sol (Max) is at 1484 ±8 and GPT-6 Astra (Max) at 1477. The best xAI model, Grok 4.20 Beta 1, is at 1475. https://essentras.com/llm-leaderboard - [2026-10-15] An aggregator reading Arena's dataset says Google has held #1 since 2026-09-30. Anthropic held #1 from 2026-02-06 to 2026-09-30, about 236 days. Before that Google held it from Oct 2025, and OpenAI before that. The aggregator counts 7 lab changes at #1 since Aug 2024. It uses the style-controlled board. https://essentras.com/llm-leaderboard - [2026-10-02] A Manifold market on the #1 company at Oct 31 recorded the Oct 2 board with Gemini 4 Argon High at 1525 ±9 and the next five all Anthropic at 1501–1505. It noted GPT-6 was not yet listed. https://manifold.markets/Terminator2/which-company-will-have-the-1-model - [2026-09-22] Anthropic released Claude Opus 5.5 on Sep 22, the first model of the 5.5 family. Sonnet 5.5 followed on Sep 28 and Haiku 5.5 on Oct 7. Opus 5.5 leads Arena WebDev at about 1811–1813 and the Artificial Analysis index at about 57.6–58. Per one aggregator it is #2 on Arena text at 1507. https://felloai.com/best-ai-models/ - [2026-10-05..11] Arena's weekly roundup (reported secondhand) has Opus 5.5 Max debuting #1 on the Agent leaderboard. It describes Anthropic as holding four of the top five text spots, and Opus 5.5 High at 1507 within about 30 points of the leader. https://www.kucoin.com/news/flash/arena-ai-model-rankings-claude-opus-5-5-max-debuts-at-top-chinese-models-maintain-mid-to-top-positions - [2026-10-16] Another aggregator, metatext.io, lists Gemini 4 Argon at 1532 as #1. I did not verify this against the Arena page. https://metatext.io/benchmarks/lmarena-elo - [2026-10-16] A Cryptobriefing item says Opus 5.5 "leads the Arena standings" ahead of GPT-6.1 Sol and cites 46% market odds for Anthropic at the end of November. This conflicts with the Arena page, which shows Google #1, and the odds figure is unverified. I treat it as low quality. https://cryptobriefing.com/anthropics-claude-opus-55-leads-ai-model-standings-user-satisfaction-key/ - [2026-10-12] Several aggregators (swfte.com, llm-stats.com) give conflicting or stale pictures, for example Claude Mythos 5 at 1531 or Grok-4.1 at the top. These do not match the Arena page and are unreliable. https://www.swfte.com/ai/lm/leaderboard - [2026-08-31] Earlier snapshot: Claude Fable 5 text was #1 at 1507 with 25.8k votes, with Opus 4.6 thinking at 1505. Anthropic was the clear leader until Gemini 4 Argon arrived around Sep 30. https://ofox.ai/blog/llm-leaderboard-best-ai-models-ranked-2026/ - [2026-10-15] Pending models. GPT-6 and GPT-6.1 Sol are already on the board but sit below the top. A "Preliminary" Gemini 4 Argon score can drift as votes accumulate, and a few more points would affect its lead. Meta's Muse Wonder also sits at #2 with only 3,247 votes. I found no announced release dates before Dec 31 for new Anthropic, OpenAI or xAI flagships. https://arena.ai/leaderboard/text BOTTOM LINE: As of Oct 15–18, Anthropic is not #1 on Arena's text board. Google's Gemini 4 Argon (High) leads Opus 5.5 (High) by about 16 points, and the 95% confidence intervals overlap, so the lead is statistically unsettled. Anthropic has the deepest bench in the top 10, and Gemini 4 Argon's score is still preliminary on about 4.9k votes. NOT FOUND: The board with the "Remove Style Control" toggle applied (the rules require checking it). The rendered page showed only the default view, with the Style Control adjustment shown as "None" in the filter list. Also not found: confirmed upcoming Anthropic, OpenAI, Google or xAI releases scheduled before Dec 31, and a reliable current price or odds figure from other venues.

- [2026-10-15] Google's Gemini 4 Argon (High) is #1 on the LMArena text board at 1,524. Meta's Muse Wonder is 15 points behind. Anthropic's best model, Claude Opus 5.5 (High), ranks 3rd at 1,508. OpenAI's best is 21st. Google has held #1 since 2026-09-30. This is an aggregator reading of LMArena, not the Arena page itself. https://essentras.com/llm-leaderboard - [2026-10-08] The saved LMArena snapshot shows Gemini 4 Argon at 1,525 ±9 on only 4,892 votes, so the score is preliminary. Claude Opus 5.5 High is 2nd at 1,507 ±8 on 6,272 votes. Anthropic holds 7 of the top 10 models and 9 of the top 20. Anthropic's deep bench makes it likely to hold the #1 spot if Google's lead shrinks. The snapshot does not say whether style control was removed. https://essentras.com/llm-leaderboard - [2026-10-15] Reference class: between 2024-08-28 and 2026-10-15, LMArena published 190 text leaderboards and the #1 lab changed 7 times. That is roughly one change per 3–4 months. Google took #1 15 days before 10-15. This is an aggregator's count and not an official figure. https://essentras.com/llm-leaderboard - [2026-10-18] Polymarket (company #1 on the Arena text board at the end of 2026) prices Anthropic at 48¢, Google at 40¢, OpenAI at 6.9¢, Meta at 2.6¢ and xAI at 1.6¢. On the same page, Polymarket's settled monthly markets show Anthropic #1 at every month's end from February to September. Google was #1 at the end of January. https://defirate.com/prediction-markets/best-ai-model-odds-this-year - [2026-10-18] Kalshi's "Best AI at the end of 2026" market (the contract in question) is described as a snapshot. It was not read as the contract's own price, as instructed. https://defirate.com/prediction-markets/best-ai-model-odds-this-year - [2026-10-07/08] Two Polymarket markets on nearly the same question disagreed. One had Anthropic 49% and Google 43%. The other, "#1 AI model end of December", had Google 40% and Anthropic 39%. Rules differ between markets, so check whether the style-control toggle matters. https://shattered.io/google-vs-anthropic-ai-prediction-markets-2026/ - [2026-10-03] Dimers' snapshot of the Kalshi market had Claude 51.9%, Gemini 37.1% and ChatGPT 9.6%. https://shattered.io/google-vs-anthropic-ai-prediction-markets-2026/ - [2026-10 trajectory] Anthropic's market odds fell from 70–80% earlier in the year to about 42–50% now. This followed Gemini 4 Argon taking #1. https://www.tipranks.com/news/why-google-is-now-favored-to-win-the-2026-ai-race-over-anthropic - [2026-10-02] The Manifold market for the end of October is at 86% Google and 7% Anthropic. Its description says five Anthropic models sit at 1,501–1,505, right behind Gemini 4 Argon. https://manifold.markets/Terminator2/which-company-will-have-the-1-model - [2026-08-31] Anthropic held #1 on the Arena text board through the summer, with claude-fable-5 at 1,507 and Anthropic models taking the next several places. Opus 5.5 took #1 on about 09-25 at 1,509, with only 2,307 votes. https://ofox.ai/blog/llm-leaderboard-best-ai-models-ranked-2026/ - [2026-10-12] Anthropic leads the Artificial Analysis Intelligence Index (Opus 5.5 at 58) and WebDev. Those are not the resolution source. https://www.therevenueaireport.com/blog/ai-model-performance-october-2026 - [2026-10-02] Scores for new releases on the Arena are volatile. In the dataset, Opus 5.5 was #1 on ~2k votes and fell to #2–3. A new Gemini or GPT-6 release before year-end could change the leader again. OpenAI's GPT-6 Sol sits near #67 on the text board. https://felloai.com/best-ai-models/ BOTTOM LINE: Anthropic held #1 on this board for most of 2026, but Google has led since 2026-09-30 by about 17 points on a thin vote count. Anthropic has the deepest bench and a ~1-in-3 to 1-in-4 base rate of #1 flips per quarter. Other venues price Anthropic roughly 40–50% and Google roughly 38–40%, with OpenAI under 10%. NOT FOUND: The live arena.ai text page with the style-control toggle removed, which is the resolution source. Whether the 'Remove Style Control' view ranks Anthropic higher than the default view. Any record of how well these markets forecast in the past.

YES means: Anthropic holds the #1 text model on Arena's text leaderboard (Remove Style Control view, ties broken by Rank (UB), then score, then votes, then earlier release) on Dec 31, 2026. - [2026-10-15] The no-style-control board, which the rules require and which colleagues could not find, is live at the URL below. Google's Gemini 4 Argon (High) is #1 at 1532 ±9 on 4,904 votes, tagged Preliminary. Claude Opus 5.5 (High) is #2 at 1516 ±7 on 8,300 votes, so the gap is 16 points. Opus 5.5's rank spread is 2–5, so Argon is clear on Rank (UB). Argon's own score is up 7 points from the style-controlled view, which cuts against a style-control path for Anthropic. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-10-15] Anthropic fills ranks 2–6 and 9 on the same raw board: Fable 5.1 (Max) 1512, Opus 5 (Max) 1508, Opus 5 (High) 1503, Opus 4.6 (High) 1502 and Opus 4.6 1498. Sonnet 5.5 (xHigh) is at 1470 on only 6.8k votes. Google's next-best entry is Gemini 3.8 Flash at 1499, so Argon is a single-model lead. The deepest-bench argument holds on this board too. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-09-26..28] Opus 5.5 (High) debuted at #1 with 1509 ±12, and Anthropic held the top six spots. It beat Opus 4.6 by only 4 points. Arena's own X post and a Sep 28 write-up confirm this. The model has since gained about 7 points on the raw board as votes accumulated (8.3k votes, 1516), so it is rising rather than fading. https://x.com/arena/status/2103893011164017018 - [2026-10-02..16] Argon's lead rests on a thin base. It has about 4.9k votes, and the count has barely moved since the Sep 30 launch (4,942, then 4,932, then 4,904). The incumbent Opus 4.6 has 77k–81k votes. One tester notes Argon's category wins sit on tiny counts, for example 255 votes in Math. A Manifold market description says new-model scores usually drift down as votes broaden. Arena publishes only boards that pass its vote thresholds, so a small vote count carries a wide ±9 interval. https://dev.to/eristoddle/gemini-4-argon-won-every-arena-category-you-cant-use-it-4fc9 - [2026-10-16] Argon's access is limited. At launch it was restricted to vetted cybersecurity teams, then rolled out to paid and Ultra users. Hands-on developer reports say Opus 5.5 is better on front-end and terminal work. Argon is only 8th in WebDev and 5th in the Agent arena. A narrower user pool could mean a different prompt mix once access widens. https://dev.to/ali_82f3409ed625e8ba8515b/gemini-4-argon-what-the-benchmarks-dont-tell-you-j46 - [2026-10-12..17] Anthropic leads on harder or non-preference measures. Opus 5.5 is #1 on the Artificial Analysis Intelligence Index at 58 against Argon's 53. It is #1 on Arena Code at about 1820 and #1 on the Agent leaderboard (Max). A Sonnet 5.5 model leads Vals Index. These are not the resolution source, but they show Anthropic's capability lead, and Arena's weights have favoured Anthropic at past releases. https://anotherwrapper.com/tools/llm-pricing/leaderboards/arena - [2026-10-15] OpenAI is not a near-term threat on this board. GPT-6.1 Sol (Max) is at about #57 with a raw score near 1448, and GPT-6 Sol sits near #67. This leaves Google as the only realistic rival, so Anthropic needs only to pass or outlast one model. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-10-15] History of reversals: the benchlm.ai month-end dataset records 21 crown changes in 42 months among 7 providers, with the longest reign 5 months. Anthropic's 2026 run of about 236 days, from the colleague report, was the longest Anthropic stretch. Leads here change hands often, and a Google lead of 16 points is smaller than recent swings. https://benchlm.ai/llm-leaderboard-history - [2026-10-16] Anthropic's release cadence supports a new Anthropic flagship before Dec 31. Releases came in Feb, Apr, May, Jun, Jul, Sep (Fable 5.1, Opus 5.5) and Sep–Oct (Sonnet 5.5, Haiku 5.5), with gaps of 2–10 weeks. A Mythos 5.5 or Fable 5.2 is rumoured but not confirmed, and Anthropic publishes no schedule. Each new Anthropic flagship has debuted at or near #1 on Arena. This is the most likely path to YES. https://aitoolsreview.co.uk/insights/next-claude-model - [2026-10-16] Most likely YES path, stated plainly. Argon's preliminary score regresses by roughly 8–15 points as its votes grow past about 20k, while Opus 5.5 (High) or Fable 5.1 (Max) holds about 1512–1516. Alternatively, a new Anthropic model (Fable 5.2 or Mythos-class) debuts at about 1520 or higher before Dec 31. Prerequisites: Google ships no stronger Gemini 4 variant, such as Pro or Ultra, and Meta's Muse Wonder (1501, 3.2k votes) stays below. Gemini 4 Argon is described as Google's first model above the Flash line, so a further Google release is a risk. https://www.therundown.ai/news/google-gemini-4-argon-benchmarks-limited-rollout - [2026-10-04..16] Anthropic's own scores on this board have been stable to rising, and the ±7 interval on Opus 5.5 is already tighter than Argon's ±9. If the true gap is near zero, the final ordering at year-end is close to a coin flip decided by sampling noise. Rank (UB) ties then go to the higher score, so the narrow-gap tie rules do not favour Anthropic. https://arena.ai/leaderboard/text/overall-no-style-control BOTTOM LINE: The strongest YES case is regression of Argon's thin, preliminary lead, or a new Anthropic flagship, with Anthropic's eight-plus top-10 entries and weeks-scale release cadence. The gap on the required no-style-control view is still 16 points, and Anthropic has no confirmed release dated before Dec 31. NOT FOUND: Any confirmed release date for a new Anthropic, Google or OpenAI flagship before Dec 31. Any record of how Argon's score changed once it gained more than 5k votes. Argon's score history on the raw board over time. A date for Argon's general availability.

YES means: Anthropic (Claude) holds the top Rank (UB) on Arena's text leaderboard on Dec 31, 2026, with "Remove Style Control" applied. Ties break on Arena Score, then votes, then earlier release. - [2026-10-15] The resolution view is now confirmed. On the no-style-control board, Gemini 4 Argon (High) is alone at #1 with rank spread 1–1, score 1532 ±9, 4,904 votes, "Preliminary". Claude Opus 5.5 (High) is #2 at 1516 ±7. Gap is 16 points. Opus 5.5 has a rank spread of 2–5, so Anthropic does not hold even a tied #1. Colleagues could only read the default view. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-10-15] On the same view, Anthropic's depth is weaker than the default-view story suggests. Fable 5.1 (Max) is 1512, Opus 5 (Max) 1508 and Opus 5 (High) 1503. Gemini 3.8 Flash (High) sits at #8 on 1499, above Opus 4.6 and Fable 5. Google has strong bench models on this board too, and no Anthropic model is within 16 points of Argon. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-10-15] The no-style-control board is more favourable to Google than the default. Argon scores 1532 here against 1524 on the default board, while Opus 5.5 scores 1516 here against 1508. The gap is 16 either way. Removing style control did not close the gap. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-10-13] Argon's general availability (API, Ultra and Pro in the Gemini app) began Oct 13. Wider public use feeds more votes and could stabilise its score, not necessarily lower it. It also became a 4-point-higher-priced model after Nov 30 ($4/$20), which is irrelevant to rank. https://cellcog.ai/blog/gemini-4-release-date/ - [2026-09-24] Google's DeepMind chief described Argon as an "early post-training output" with fast iteration to follow. That points to a stronger Gemini 4 update (a Pro or Deep Think variant) before year-end. Anthropic would have to beat that moving target, not a fixed Argon. Google has also repeatedly said releases are staged. https://9to5google.com/2026/09/24/google-says-gemini-4-release-is-coming-as-soon-as-possible/ - [2026-10-14] Reported reception supports Argon's lead being real. It is #1 in Text Arena's coding, hard prompts, instruction-following and creative-writing categories. Techzine notes it leads Vals Index. Its weaknesses (WebDev #9, Agent #5) are not what the overall text board scores. Anthropic's strengths (WebDev, Agent #1, Artificial Analysis) do not feed the resolution metric. https://www.techzine.eu/news/applications/144960/opinions-are-divided-on-gemini-4-argon/ - [2026-10-15] Style control is not the Anthropic lever. Anthropic's edge has been in agentic and coding leaderboards. Opus 5.5 (Max) leads Agent at 18.9%, with Argon fifth. Text-preference voters rated Argon higher. That is a structural reason Anthropic's agent and coding strength does not translate to text. https://arena.ai/leaderboard - [2026-10-18] Kalshi's own page shows the year-end contract resolving Dec 31 at 8:00 am EST, with Claude shown as a favourite but not a majority. Resolution is a single snapshot, so any Gemini or OpenAI release in the final weeks matters more than the monthly history. Prior Anthropic months at #1 are no help to Yes. https://kalshi.com/markets/kxllm1/yearend-top-llm/kxllm1-26dec31 - [2026-10-18] Contract-tie wording works against a fragmented Anthropic. A Kalshi sibling contract (top-ranked before 2027) says a tie fails the payout criterion. The year-end contract instead breaks ties by score. Anthropic's many models can share UB rank 1 with each other, but a lone higher-scored Gemini model takes UB #1 outright. https://www.oddsshopper.com/articles/prediction-markets/top-ranked-ai-model-2026-model-verdict - [2026-10-18] The sibling Kalshi Oct 31 market priced Argon at about 70% (Anthropic's Opus 5.5 about 2%), down 6 points in the week to Oct 18. That shows the market treats the Argon lead as durable at least for the near term, and it checks the same no-style-control view. https://defirate.com/odds/best-ai-model/ - [2026-10-15] Rivals' risks to Anthropic are broader than just Google. GPT-6.1 Sol (Max) is on the board at 1448 or lower on this view, so OpenAI is not an immediate threat. Meta's Muse Wonder (Max) is at 1501 ±11 on only 3,247 votes. More Meta votes could move it either way. https://arena.ai/leaderboard/text/overall-no-style-control - [2026-10-02] New-model scores often drift down. A Manifold note says Argon's score might fall 15+ points as votes accumulate, but that is a hypothesis. Argon's votes were 4,892 on Oct 8 and 4,904 on Oct 15. The score rose from 1525 to 1532 on this view, and vote growth is slow. The lead has not eroded in two weeks of data. https://manifold.markets/Terminator2/which-company-will-have-the-1-model BOTTOM LINE: Anthropic is #2 on the exact resolution view, 16 points behind with a lone UB #1 ahead of it, and Google is signalling further Gemini 4 releases before Dec 31. Anthropic needs either a new flagship that overtakes Argon or Argon's score to drift down about 16 points. Nothing in the Argon scoring history so far shows that drift. NOT FOUND: Any announced Anthropic flagship release date before Dec 31. Any historical record of how Argon-type preliminary scores drift on this board. A verified date for the next Gemini 4 variant.