One agent session
1M input tokens and 100K output tokens, no caching.
- Input1M x $10 = $10.00
- Output0.1M x $50 = $5.00
$15.00per session
Anthropic - Closed weights
Claude Mythos 5 pricing and specs
Claude Mythos 5 is a closed-weights model from Anthropic that costs $10 per 1M input tokens and $50 per 1M output tokens on the first-party API, with a 1M-token context window.
Last verified from platform.claude.com. All sources
- Input / 1M
- $10
- Output / 1M
- $50
- Context
- 1M tokens
- Weights
- Closed
Pricing per 1M tokens
| Item | Price / 1M tokens |
|---|---|
| Input | $10 |
| Output | $50 |
| Cache read | $1 |
| Cache write (5 minutes) | $12.50 |
| Cache write (1 hour) | $20 |
| Batch inputBatch requests | $5 |
| Batch outputBatch requests | $25 |
Note: Verification required: offered for defensive cybersecurity work only to organizations verified through Anthropic's verification programs; the pricing page marks it limited availability. Same model, specifications and prices as Claude Fable 5. Not listed in the Vercel AI Gateway model list on 2026-10-17, so it has no Vercel AI Gateway id.
Specs
- Context window
- 1,000,000 tokens
- Max output
- 128,000 tokens
- Release date
- Provider
- Anthropic
- API model id
claude-mythos-5- Weights
- Closed weights
What Claude Mythos 5 costs in practice
Worked from the standard list rates above, with the math shown so you can swap in your own token counts.
A chat app
10,000 requests a day at 2K input and 500 output tokens each.
- Input20M x $10 = $200.00
- Output5M x $50 = $250.00
$450.00per day
$13,500.00 per 30-day month
The same session at a 90% cache hit
90% of the input is read from the prompt cache. The one-time cache write premium is not included.
- Cached input0.9M x $1 = $0.90
- Uncached input0.1M x $10 = $1.00
- Output0.1M x $50 = $5.00
$6.90per session
Compare with
| Model | Input / 1M | Output / 1M |
|---|---|---|
| Claude Mythos 5 (this page) | $10 | $50 |
| Claude Fable 5Anthropic | $10 | $50 |
| Claude Fable 5.1Anthropic | $10 | $50 |
| Claude Mythos 5.1Anthropic | $10 | $50 |
| GPT-6 AstraOpenAI | $10 | $50 |
| Claude Opus 4.5Anthropic | $5 | $25 |
| Claude Opus 4.6Anthropic | $5 | $25 |
| Claude Opus 4.7Anthropic | $5 | $25 |
Compare
Side-by-side pages with both models' prices, specs, cost examples and like-for-like benchmark rows.
Related reading
- Claude Mythos and Fable 5 Banned: The Export Controls That Shut Down Two Frontier ModelsClaude Fable 5 and Mythos 5 were suspended for all users by a US export control directive. What it said, why it hit everyone, and what changed for developers.
- Claude Mythos vs Fable 5: What Is the Difference?Claude Mythos 5 vs Fable 5 explained. They are the same underlying model with different access and safeguards, which is why both were suspended together.
- Claude Mythos 5 Explained: What It Is, Who Can Access It, and Why It's GatedClaude Mythos 5 explained - how it differs from Fable 5, who gets unrestricted access through Project Glasswing, and what developers should do right now.
- Claude Agent SDK in Late 2026: What Is New and How to Use ItWhat changed in the Claude Agent SDK by October 2026: nested subagents with caps, SessionStore, skills, plugins, structured outputs and permission defaults.
- Claude API OpenTelemetry Tracing: How to Set It Up (Beta)The Claude API now exports OpenTelemetry traces in beta. Set up SDK spans in code, add a Console destination for API spans, and count tokens once.
- Claude Code Idle Compaction: What It Does and How to Turn It OffClaude Code 2.1.299 compacts sessions over 200K tokens after about 54 idle minutes. How the cache math works, the setting to turn it off, and when to keep it.
FAQ
How much does Claude Mythos 5 cost per million tokens?
Claude Mythos 5 costs $10 per 1M input tokens and $50 per 1M output tokens on Anthropic's first-party API, per platform.claude.com on October 17, 2026. Per 1M tokens, cache reads cost $1, and the batch rate is $5 input and $25 output.
What is Claude Mythos 5's context window?
Claude Mythos 5 has a 1,000,000-token context window and returns up to 128,000 output tokens per response.
Are Claude Mythos 5's weights open?
No. Claude Mythos 5 is a closed-weights model. You call it through Anthropic's API as claude-mythos-5.
When was Claude Mythos 5 released?
Anthropic released Claude Mythos 5 on June 9, 2026.
Sources
Last verified from platform.claude.com.
- https://platform.claude.com/docs/en/about-claude/pricing
- https://platform.claude.com/docs/en/models/mythos-5/overview
- https://platform.claude.com/docs/en/about-claude/models/overview
- https://platform.claude.com/docs/en/release-notes/overview
- https://platform.claude.com/docs/en/about-claude/model-deprecations
Newsletter
Get model price changes as they ship
One email per week. New model releases, price cuts and what they mean for your bill.