Model Watch · Anthropic
Claude Opus 5.1
Not out yet, and no release date announced. There is no Opus 5.1. Opus 5 shipped in July and the 5.1 generation went out as Fable and Mythos, so this entry exists to catch the name if it ever turns up.
What is Claude Opus 5.1 capable of?
3 posts from people showing what they made with Claude Opus 5.1, newest and most-reacted first. People are posting game made with it.
Each card is the original post, shown the way X or Reddit embeds it, with a link to where it came from. We picked the ones that show something being made and skipped the benchmark screenshots. We can't vouch for any of them being unedited.
What is Claude Opus 5.1?
Claude Opus 5.1 is a model from Anthropic, built in the US. Nobody at the lab has confirmed it. Everything below is other people talking.
When is Claude Opus 5.1 coming?
No date. Anthropic hasn't given one, so we haven't made one up. The mentions further down are where a date would show up first.
What does it cost, and how much context does it hold?
No price and no context window. Anthropic hasn't published either, and we're not going to estimate them for you. This table fills in when they do.
| Lab | Anthropic |
|---|---|
| Built in | US |
| Status | rumoured |
| API model id | Not published |
| Released | Not yet |
| Context window | Not published |
| Max output | Not published |
| Input, per 1M tokens | Not published |
| Output, per 1M tokens | Not published |
How does it compare to Anthropic's other models?
| Model | Status | Date | Context | In / 1M | Out / 1M |
|---|---|---|---|---|---|
| Claude Opus 5.1 | rumoured | — | — | — | — |
| Claude Mythos 5.1 | released | 1 September 2026 | 1M tokens | $10.00 | $50.00 |
| Claude Fable 5.1 | released | 1 September 2026 | 1M tokens | $10.00 | $50.00 |
| Claude Opus 5 | released | 24 July 2026 | 1M tokens | $5.00 | $25.00 |
| Claude Sonnet 5 | released | 30 June 2026 | 1M tokens | $2.00 | $10.00 |
| Claude Fable 5 | released | 9 June 2026 | 1M tokens | $10.00 | $50.00 |
| Claude Opus 4.5 | released | 24 November 2025 | 200K tokens | $5.00 | $25.00 |
| Claude Haiku 4.5 | released | 15 October 2025 | 200K tokens | $1.00 | $5.00 |
| Claude Sonnet 4.5 | released | 29 September 2025 | 200K tokens | $3.00 | $15.00 |
| Claude Opus 4.1 | deprecated | — | — | $15.00 | $75.00 |
A dash means the lab hasn't published that number for that model.
What are people discussing about Claude Opus 5.1?
We tracked 25 public discussions naming Claude Opus 5.1 across r/Anthropic, r/ChatGPT, r/ClaudeAI and r/ClaudeCode and 8 other communities between 4 August 2026 and 12 September 2026.
The subject that came up most was using it to write code, then availability and outages. A discussion can cover several, so these add up to more than 25.
| What people are discussing | Threads |
|---|---|
| using it to write code | 4 |
| availability and outages | 1 |
| what it costs | 1 |
Every mention we've logged
Every tracked post, release, changelog entry or incident whose title or summary names Claude Opus 5.1. Newest first, each one linking to where the lab published it.
Nothing yet. The name hasn't appeared in a tracked source.
Claude Opus 5.1 is part of the Claude 5 family, which is where the point releases sit next to each other.
Keep reading
The release timeline is every model we know about, filterable by lab, country and date. The tracker is the live feed these mentions come from, and Model Watch is the whole catalogue on one page.
More from Anthropic:
- Claude Mythos 5.1 · released
- Claude Fable 5.1 · released
- Claude Opus 5 · released
- Claude Sonnet 5 · released
- Claude Fable 5 · released
- Claude Opus 4.5 · released
- Claude Haiku 4.5 · released
- Claude Sonnet 4.5 · released
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