Anthropic · Released Jun 9, 2026Claude Mythos 5
Restricted Claude model for advanced cybersecurity and biology research workflows.
- Capability
- —No ECI score yet
- Input
- $10.00per 1M tokens
- Output
- $50.00per 1M tokens
- Context
- 1M128K max output
What it costs
- Input
- $10.00per million tokens
- Output
- $50.00per million tokens
- Blended (3:1)
- $20.00pricier than 96% of priced models
Typical monthly bills
| Monthly usage | Estimated cost |
|---|---|
| Side project2M input + 0.5M output tokens | $45.00 |
| Team assistant25M input + 5M output tokens | $500.00 |
| Production app250M input + 50M output tokens | $5,000 |
Median of 2 paid API providers on models.dev.
Independent benchmarks
Epoch AI has not published a Capabilities Index score for Claude Mythos 5 yet.
The details
- Lab
- Anthropic
- Released
- Jun 9, 2026
- Knowledge cutoff
- Jan 31, 2026
- Context window
- 1,000,000 tokens
- Max output
- 128,000 tokens
- Inputs
- Text, Images, PDFs
- Output
- Text
- Reasoning
- Always on
- Tool calling
- Yes
- Structured output
- Yes
- Weights
- Proprietary
- Availability
- 2 API providerslisted on models.dev
More from Anthropic
About Claude Mythos 5
How much does Claude Mythos 5 cost?
Claude Mythos 5 costs $10.00 input / $50.00 output per million tokens (median across 2 API providers). At a 3:1 input-to-output mix that is $20.00 per million tokens, more expensive than 96% of the 360 priced models we track.
What is the context window of Claude Mythos 5?
Claude Mythos 5 accepts up to 1,000,000 tokens per request and can write up to 128,000 tokens in one response.
How good is Claude Mythos 5?
Epoch AI has not published a Capabilities Index score for Claude Mythos 5 yet.
Is Claude Mythos 5 open source?
No. Claude Mythos 5 is proprietary; you use it through an API or partner platforms.
What inputs does Claude Mythos 5 support?
Claude Mythos 5 accepts text, images and PDFs and replies in text. It is a reasoning model, supports tool calling and can return structured JSON output.
When was Claude Mythos 5 released?
Anthropic released Claude Mythos 5 on Jun 9, 2026. Its training data runs to Jan 31, 2026.
What are the best alternatives to Claude Mythos 5?
The closest current models from other labs on capability, price and release date are GPT-5.6 Cyber (OpenAI, $12.50 / $75.00), Fugu Ultra (Sakana AI, $5.00 / $30.00), DiffusionGemma 26B A4B IT (Google) and MAI-Code-1-Flash (Microsoft).