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GPT-6.1 Sol vs Claude Opus 5.5
Claude Opus 5.5 scores higher than GPT-6.1 Sol on all 6 public leaderboards that rate both. On the ArtificialWatch Index, which takes the median of each model's percentile across the boards that score it, GPT-6.1 Sol is at 88.2 and Claude Opus 5.5 at 100 (out of 100).
Scores as published by each board; table composed October 8, 2026.
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Leaderboard by leaderboard
| Board | GPT-6.1 Sol | Claude Opus 5.5 | Higher |
|---|---|---|---|
| LMArena Elo (community votes) | 1,755.4 | 1,813 | Claude Opus 5.5 |
| LiveBench global average (0-100) | 81.6 | 83.2 | Claude Opus 5.5 |
| SimpleBench AVG@5 % (private set) | 82.9 | 88.4 | Claude Opus 5.5 |
| LLM Stats LLM Stats Score · composite (0-100), their rendered top 15 | 53.9 | 60.4 | Claude Opus 5.5 |
| Vals AI Vals Index accuracy % · weighted finance + coding tasks | 61.2 | 67 | Claude Opus 5.5 |
| Artificial Analysis intelligence index · measured runs only | 51.8 | 57.6 | Claude Opus 5.5 |
Raw scores are each board's own scale, so compare within a row, not across rows. Full table: the bench index.
For coding
On the ArtificialWatch coding index, GPT-6.1 Sol is at 82.4 (#6 of 35) and Claude Opus 5.5 at 96.9 (#1). Claude Opus 5.5 scores higher on all 3 coding boards that rate both.
| Coding board | GPT-6.1 Sol | Claude Opus 5.5 |
|---|---|---|
| LMArena · Coding | 1,545.3 | 1,549.5 |
| LiveBench · Coding | 68.8 | 80.5 |
| Vals Vibe Code Bench | 88.9 | 90.3 |
GPT-6.1 Sol at a glance
- Developer
- OpenAI
- Status
- Live since September 29, 2026
- API price
- $2 input / $10 output per 1M tokens · OpenAI, gpt-6.1-sol
- Context window
- 1.05M tokens
Live — Sep 29, launched at DevDay · Ultrafast tier open to all API users Oct 8 at $12/$60 (six times standard, OpenAI's pricing page) · $2/$10 per 1M, cached input $0.10 (half of GPT-6 Sol's) · in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise and Edu, not yet in Chat · OpenAI says it nearly matches GPT-6 Astra on agentic coding, computer use and professional work at a fifth of Astra's price · Artificial Analysis Intelligence Index 52 at max effort, #10 of 221 reasoning models (read Sep 29) · 1.05M ctx as OpenRouter lists it, which also carries gpt-6.1-sol-pro (the same model in a pro reasoning mode) · Ultrafast (up to 8x faster in Codex) 'in the coming days' · our sweep read gpt-6.1-sol on OpenAI's public model docs at 17:23 UTC and fired at 17:24, about 20 minutes after the keynote.
GPT-6.1 Sol Ultrafast opens to every API user at $12 / $60, six times standard Sol
2026-10-08 · OpenAI's Ultrafast tier now covers GPT-6.1 Sol for every API user. OpenAI's API docs, read on October 8, say Ultrafast mode is "broadly available" for GPT-6 Astra and GPT-6.1 Sol and "available to all API users", with preview access for GPT-5.6 Sol.
GPT-6.1 Sol ships at DevDay at $2/$10, and OpenAI says it nearly matches Astra
2026-09-29 · OpenAI launched GPT-6.1 Sol at its DevDay keynote on September 29. It is available now in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise and Edu users, not yet in Chat, and in the API as gpt-6.1-sol.
Claude Opus 5.5 at a glance
- Developer
- Anthropic
- Status
- Live since September 22, 2026
- API price
- $4 input / $20 output per 1M tokens · Anthropic, claude-opus-5-5
- Context window
- 1M tokens
Live — Sep 22 · $4/$20 per MTok, down from Opus 5 at $5/$25 · 1M ctx / 128K out · adaptive thinking always on, default effort medium · cache reads 5% of base input · Anthropic now says start here for most workloads, and Opus 5 is legacy.
Claude Opus 5.5 ships at $4/$20 - and that is LESS than the Opus 5 it replaces
2026-09-22 · Claude Opus 5.5 is live. Our sweep read the id claude-opus-5-5 at 16:24:44 UTC on September 22 and the alert went out at 16:25:45 - 61 seconds later, to 307 inboxes and one phone. The hunt that caught it was armed the previous day, before the model had a confirmed name, on the version range rather than on the rumour.
Markets put the next Claude Opus at 83% by Thursday — the name going around is 5.5
2026-09-21 · Polymarket's "Next Claude Opus released by...?" book, read directly at 06:49 UTC, September 21: 83% by September 24, 91% by September 27, 95% by September 30. Polymarket's own post about nine hours earlier had Thursday at 72%, so the number has been climbing through the day.
GPT-6.1 Sol vs Claude Opus 5.5: quick answers
Which is better, GPT-6.1 Sol or Claude Opus 5.5?
It depends on what you measure. Claude Opus 5.5 scores higher than GPT-6.1 Sol on all 6 public leaderboards that rate both. Claude Opus 5.5's widest lead is on LLM Stats. On the ArtificialWatch Index, which takes the median of each model's percentile across the boards that score it, GPT-6.1 Sol is at 88.2 and Claude Opus 5.5 at 100 (out of 100).
Which is newer, GPT-6.1 Sol or Claude Opus 5.5?
GPT-6.1 Sol. It went live on September 29, 2026, 7 days after Claude Opus 5.5 (September 22, 2026).
Which is cheaper, GPT-6.1 Sol or Claude Opus 5.5?
GPT-6.1 Sol is cheaper on both input and output. On each vendor's own API, GPT-6.1 Sol is $2 input / $10 output per million tokens and Claude Opus 5.5 is $4 input / $20 output per million tokens. GPT-6.1 Sol's rate rises for prompts over 272K tokens. Prices as published in the models.dev catalog, as of 2026-10-08.
Which has the bigger context window, GPT-6.1 Sol or Claude Opus 5.5?
GPT-6.1 Sol, at 1.05M tokens against Claude Opus 5.5's 1M, as each vendor lists it.
How do GPT-6.1 Sol and Claude Opus 5.5 compare for coding?
On the ArtificialWatch coding index, GPT-6.1 Sol is at 82.4 (#6 of 35) and Claude Opus 5.5 at 96.9 (#1). Claude Opus 5.5 scores higher on all 3 coding boards that rate both.
Who makes GPT-6.1 Sol and Claude Opus 5.5?
GPT-6.1 Sol is from OpenAI; Claude Opus 5.5 is from Anthropic.
Where do these numbers come from?
Each score is the leaderboard's own published figure, read by ArtificialWatch (table composed October 8, 2026). Boards measure different things, so raw scores are only comparable within a row.
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