LiteLLMModels

Claude Mythos 5.1 API Pricing

As of October 10, 2026, Claude Mythos 5.1 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens on Anthropic, with cache reads at $0.25 and cache writes at $12.50 per 1M tokens. It has a 1,000,000-token context window and returns up to 128,000 tokens per response.

By AnthropicModel ID claude-mythos-5-1Prices updated Checked
Input
$10.00 / 1M tokens
Output
$50.00 / 1M tokens
Cache read
$0.25 / 1M tokens
Context window
1,000,000 tokens
Max output
128,000 tokens
Providers
2
Added to LiteLLM
September 3, 2026

Claude Mythos 5.1 pricing by provider

4 listings across 2 providers. Token prices are in US dollars per 1M tokens. The highlighted row is the price quoted above.

ProviderModel name in LiteLLMInputOutputCache readCache writeBatch inBatch outContext
Anthropicclaude-mythos-5-1$10.00$50.00$0.25$12.50$5.00$25.001M
Amazon Bedrockanthropic.claude-mythos-5-1$10.00$50.00$0.25$12.50––1M
Amazon BedrockGlobal cross-regionglobal.anthropic.claude-mythos-5-1$10.00$50.00$0.25$12.50––1M
Amazon BedrockUS cross-regionus.anthropic.claude-mythos-5-1$11.00$55.00$0.275$13.75––1M

Other Claude Mythos 5.1 prices on Anthropic

Cache write, 1 hour$20.00 per 1M tokens
Web search$10.00 per 1K searches

What Claude Mythos 5.1 costs in practice

1,000 requests with 2,000 input and 500 output tokens each

Anthropic$45.00
Amazon Bedrock$45.00
Anthropic batch$22.50

100 long-document requests with 100,000 input and 2,000 output tokens each

Anthropic$110.00
Amazon Bedrock$110.00

Claude Mythos 5.1 features

Use Claude Mythos 5.1 with LiteLLM

Call Claude Mythos 5.1 through the LiteLLM Python SDK, or put it behind the LiteLLM proxy and send OpenAI-format requests to /v1/chat/completions. LiteLLM tracks the cost of every request at these prices.

Python SDK
from litellm import completion

response = completion(
    model="claude-mythos-5-1",
    messages=[{"role": "user", "content": "Hello!"}],
)
Proxy config.yaml
model_list:
  - model_name: claude-mythos-5-1
    litellm_params:
      model: claude-mythos-5-1
      api_key: os.environ/ANTHROPIC_API_KEY
Call the proxy
curl http://0.0.0.0:4000/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer sk-1234" \
  -d '{
    "model": "claude-mythos-5-1",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Claude Mythos 5.1 FAQ

How much does Claude Mythos 5.1 cost?

Claude Mythos 5.1 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens on Anthropic, with cache reads at $0.25 and cache writes at $12.50 per 1M tokens. Batch requests cost $5.00 per 1M input tokens and $25.00 per 1M output tokens.

What is the context window of Claude Mythos 5.1?

Claude Mythos 5.1 has a 1,000,000-token context window and returns up to 128,000 tokens per response.

Which providers offer Claude Mythos 5.1?

Claude Mythos 5.1 is available from 2 providers through LiteLLM: Anthropic and Amazon Bedrock.

How do I call Claude Mythos 5.1 with an OpenAI-compatible API?

Use the LiteLLM Python SDK with model="claude-mythos-5-1", or add the model to the LiteLLM proxy's config.yaml and send requests to /v1/chat/completions from any OpenAI client. LiteLLM tracks the cost of every request at the prices on this page.

What features does Claude Mythos 5.1 support?

Claude Mythos 5.1 supports function calling, structured output, image input, PDF input, reasoning, prompt caching and computer use.

When did LiteLLM add Claude Mythos 5.1?

Claude Mythos 5.1 was added to LiteLLM's model price file on September 3, 2026.

Sources

Prices come from LiteLLM's open-source model_prices_and_context_window.json, which LiteLLM uses to calculate the cost of every request. Provider pricing pages:

LiteLLM docs: Anthropic, Amazon Bedrock.

Provider pages: Anthropic, Amazon Bedrock.