Model Tracker
Claude Mythos Preview
Claude Mythos Preview is an AI model made by Anthropic. Anthropic released it on April 2026. Its context window is 1,000,000 tokens.
Claude Mythos Preview is an AI model made by Anthropic. Anthropic released it on April 2026. Its context window is 1,000,000 tokens. Its longest answer is 128,000 tokens. Through the API it costs $25.00 per 1M tokens for input and $125.00 per 1M tokens for output.
- Released
- April 2026 — www.anthropic.com, read 16 October 2026
- Status
- Not confirmed: two readings disagree: deprecated and preview
- Takes
- Not confirmed: two readings disagree: text, image and text, code
- Returns
- Text — www.anthropic.com, read 16 October 2026
- Open weights
- Not confirmed: The reviewed official pages do not state whether the model’s weights are open or downloadable.
- Licence
- Not confirmed: The reviewed official pages do not name a licence for this model.
- Context window
- 1,000,000 tokens — platform.claude.com, read 16 October 2026
- Longest answer
- 128,000 tokens — platform.claude.com, read 16 October 2026
- Knowledge cutoff
- Not confirmed: The reviewed official pages do not state a knowledge cutoff for Claude Mythos Preview.
- API price, input
- $25.00 per 1M tokens — www.anthropic.com, read 16 October 2026
- API price, output
- $125.00 per 1M tokens — www.anthropic.com, read 16 October 2026
- Where
- Not confirmed: two readings disagree: api, cloud and api
- Parameters
- Not confirmed: The reviewed official pages do not publish a parameter count for this model.
- Model card
- https://www-cdn.anthropic.com/8b8380204f74670be75e81c820ca8dda846ab289.pdf — platform.claude.com, read 16 October 2026
Questions
When was Claude Mythos Preview released?
Anthropic released Claude Mythos Preview on April 2026.
What is the context window of Claude Mythos Preview?
The context window of Claude Mythos Preview is 1,000,000 tokens, as Anthropic prints it.
How much does the Claude Mythos Preview API cost?
On the standard tier, Claude Mythos Preview costs $25.00 per 1M tokens for input and $125.00 per 1M tokens for output, as Anthropic lists it.
More from Anthropic
- Claude 1.0
- Claude 1.1
- Claude 1.2
- Claude 1.3
- Claude 2
- Claude 2.1
- Claude 3 Haiku
- Claude 3 Opus
- Claude 3 Sonnet
- Claude 3.5 Haiku
- Claude Fable 5
- Claude Fable 5.1
- Claude Haiku 4.5
- Claude Haiku 5.5
- Claude Instant 1.0
- Claude Instant 1.1
- Claude Instant 1.2
- Claude Opus 4.1
- Claude Opus 4.5
- Claude Opus 4.6
- Claude Opus 4.7
- Claude Opus 4.8
- Claude Opus 5
- Claude Opus 5.5
Sources
- Project Glasswing (read 16 October 2026)
- Anthropic’s Transparency Hub (read 16 October 2026)
- Model deprecations (read 16 October 2026)
- Context windows (read 16 October 2026)
- Model cards (read 16 October 2026)