OpenAI’s GPT-6 Astra, released September 3, 2026, quickly claimed the top spot on the Code Arena WebDev leaderboard with a 1,797 Elo score, 35 points ahead of Anthropic’s Claude Fable 5.1. This crowdsourced benchmark evaluates large language models on iterative, multi-step frontend and agentic web development tasks through community votes, making recent performance gains especially influential for end-of-September resolution. The model’s edge in tool use and real-world coding workflows has shifted trader consensus sharply toward OpenAI, while Anthropic’s earlier September 1 release of Fable 5.1 now trails. Lower-probability contenders such as Google, Alibaba, and Meta remain further back on the same leaderboard, with no major updates reported in the past week that would alter current positioning before month-end.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedOpenAI 83.4%
Anthropic 15%
SpaceXAI <1%
Google <1%
$126,310 Vol.
$126,310 Vol.
Sep 30, 2026
OpenAI
83%
Anthropic
15%
SpaceXAI
1%
1%
Moonshot
<1%
Meta
<1%
Alibaba
<1%
Z.ai
<1%
ByteDance
<1%
MiniMax
<1%
Xiaomi
<1%
DeepSeek
<1%
Thinky
<1%
Tencent
<1%
Poolside
<1%
Mistral
<1%
OpenAI 83.4%
Anthropic 15%
SpaceXAI <1%
Google <1%
$126,310 Vol.
$126,310 Vol.
Sep 30, 2026
OpenAI
$21,777 Vol.
83%
Anthropic
$51,964 Vol.
15%
SpaceXAI
$5,486 Vol.
1%
$4,324 Vol.
1%
Moonshot
$19,269 Vol.
<1%
Meta
$3,037 Vol.
<1%
Alibaba
$7,415 Vol.
<1%
Z.ai
$4,750 Vol.
<1%
ByteDance
$1,134 Vol.
<1%
MiniMax
$1,246 Vol.
<1%
Xiaomi
$657 Vol.
<1%
DeepSeek
$2,690 Vol.
<1%
Thinky
$560 Vol.
<1%
Tencent
$571 Vol.
<1%
Poolside
$641 Vol.
<1%
Mistral
$789 Vol.
<1%
This market will resolve according to the company that owns the model that has the highest rank based on the arena.ai Code Arena | WebDev Leaderboard when the table under "Code Arena | WebDev" filtered for "Models" is checked on September 30, 2026, 12:00 PM ET.
Results from the "Rank" column under the "Code Arena | WebDev" Leaderboard tab at https://arena.ai/leaderboard/code/webdev (Overall) filtered for "Models" will be used to resolve this market.
Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by which model is listed higher on the leaderboard. If a tie still remains, alphabetical order of company names as listed in this market group will be used as a final tiebreaker (e.g., “Google” would be ranked ahead of “SpaceXAI”). This market will resolve based on the company that occupies first place under this ranking.
The resolution source for this market is the arena.ai Code Arena | WebDev Leaderboard. If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".OpenAI’s GPT-6 Astra, released September 3, 2026, quickly claimed the top spot on the Code Arena WebDev leaderboard with a 1,797 Elo score, 35 points ahead of Anthropic’s Claude Fable 5.1. This crowdsourced benchmark evaluates large language models on iterative, multi-step frontend and agentic web development tasks through community votes, making recent performance gains especially influential for end-of-September resolution. The model’s edge in tool use and real-world coding workflows has shifted trader consensus sharply toward OpenAI, while Anthropic’s earlier September 1 release of Fable 5.1 now trails. Lower-probability contenders such as Google, Alibaba, and Meta remain further back on the same leaderboard, with no major updates reported in the past week that would alter current positioning before month-end.
This market will resolve according to the company that owns the model that has the highest rank based on the arena.ai Code Arena | WebDev Leaderboard when the table under "Code Arena | WebDev" filtered for "Models" is checked on September 30, 2026, 12:00 PM ET.
Results from the "Rank" column under the "Code Arena | WebDev" Leaderboard tab at https://arena.ai/leaderboard/code/webdev (Overall) filtered for "Models" will be used to resolve this market.
Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by which model is listed higher on the leaderboard. If a tie still remains, alphabetical order of company names as listed in this market group will be used as a final tiebreaker (e.g., “Google” would be ranked ahead of “SpaceXAI”). This market will resolve based on the company that occupies first place under this ranking.
The resolution source for this market is the arena.ai Code Arena | WebDev Leaderboard. If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".
Results from the "Rank" column under the "Code Arena | WebDev" Leaderboard tab at https://arena.ai/leaderboard/code/webdev (Overall) filtered for "Models" will be used to resolve this market.
Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by which model is listed higher on the leaderboard. If a tie still remains, alphabetical order of company names as listed in this market group will be used as a final tiebreaker (e.g., “Google” would be ranked ahead of “SpaceXAI”). This market will resolve based on the company that occupies first place under this ranking.
The resolution source for this market is the arena.ai Code Arena | WebDev Leaderboard. If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".
Market Opened: Jul 20, 2026, 7:23 PM ET
Volume
$126,310End Date
Oct 1, 2026Market Opened
Jul 20, 2026, 7:23 PM ETResolution Source
https://arena.ai/leaderboard/code/webdevResolver
0x69c47De9D...This market will resolve according to the company that owns the model that has the highest rank based on the arena.ai Code Arena | WebDev Leaderboard when the table under "Code Arena | WebDev" filtered for "Models" is checked on September 30, 2026, 12:00 PM ET.
Results from the "Rank" column under the "Code Arena | WebDev" Leaderboard tab at https://arena.ai/leaderboard/code/webdev (Overall) filtered for "Models" will be used to resolve this market.
Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by which model is listed higher on the leaderboard. If a tie still remains, alphabetical order of company names as listed in this market group will be used as a final tiebreaker (e.g., “Google” would be ranked ahead of “SpaceXAI”). This market will resolve based on the company that occupies first place under this ranking.
The resolution source for this market is the arena.ai Code Arena | WebDev Leaderboard. If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".OpenAI’s GPT-6 Astra, released September 3, 2026, quickly claimed the top spot on the Code Arena WebDev leaderboard with a 1,797 Elo score, 35 points ahead of Anthropic’s Claude Fable 5.1. This crowdsourced benchmark evaluates large language models on iterative, multi-step frontend and agentic web development tasks through community votes, making recent performance gains especially influential for end-of-September resolution. The model’s edge in tool use and real-world coding workflows has shifted trader consensus sharply toward OpenAI, while Anthropic’s earlier September 1 release of Fable 5.1 now trails. Lower-probability contenders such as Google, Alibaba, and Meta remain further back on the same leaderboard, with no major updates reported in the past week that would alter current positioning before month-end.
This market will resolve according to the company that owns the model that has the highest rank based on the arena.ai Code Arena | WebDev Leaderboard when the table under "Code Arena | WebDev" filtered for "Models" is checked on September 30, 2026, 12:00 PM ET.
Results from the "Rank" column under the "Code Arena | WebDev" Leaderboard tab at https://arena.ai/leaderboard/code/webdev (Overall) filtered for "Models" will be used to resolve this market.
Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by which model is listed higher on the leaderboard. If a tie still remains, alphabetical order of company names as listed in this market group will be used as a final tiebreaker (e.g., “Google” would be ranked ahead of “SpaceXAI”). This market will resolve based on the company that occupies first place under this ranking.
The resolution source for this market is the arena.ai Code Arena | WebDev Leaderboard. If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".
Results from the "Rank" column under the "Code Arena | WebDev" Leaderboard tab at https://arena.ai/leaderboard/code/webdev (Overall) filtered for "Models" will be used to resolve this market.
Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by which model is listed higher on the leaderboard. If a tie still remains, alphabetical order of company names as listed in this market group will be used as a final tiebreaker (e.g., “Google” would be ranked ahead of “SpaceXAI”). This market will resolve based on the company that occupies first place under this ranking.
The resolution source for this market is the arena.ai Code Arena | WebDev Leaderboard. If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".
Volume
$126,310End Date
Oct 1, 2026Market Opened
Jul 20, 2026, 7:23 PM ETResolution Source
https://arena.ai/leaderboard/code/webdevResolver
0x69c47De9D...OpenAI’s GPT-6 Astra, released September 3, 2026, quickly claimed the top spot on the Code Arena WebDev leaderboard with a 1,797 Elo score, 35 points ahead of Anthropic’s Claude Fable 5.1. This crowdsourced benchmark evaluates large language models on iterative, multi-step frontend and agentic web development tasks through community votes, making recent performance gains especially influential for end-of-September resolution. The model’s edge in tool use and real-world coding workflows has shifted trader consensus sharply toward OpenAI, while Anthropic’s earlier September 1 release of Fable 5.1 now trails. Lower-probability contenders such as Google, Alibaba, and Meta remain further back on the same leaderboard, with no major updates reported in the past week that would alter current positioning before month-end.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
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