Claude Mythos 5.1
Fresh input / cached input / output cost breakdown, active and scheduled rates, provenance, same-model deployment markup, and cost-comparable alternatives for this purchasable lane.
Illustrative workloads
Pick a useful starting shape, then fine-tune every input below.
Workload and pricing scenario
Adjust the token shape, cache behavior, time window, and service tier. Every number below updates immediately.
Workload cost calculator
Share of input tokens served from cache. Applied only to models with a cache meter.
Rows with a rate that changes by time of day, promo window or service tier are priced for this scenario instead of their flat listed rate; a brand-colored label under the model name names which one applies. Context size for band-priced rows uses the input-token count below.
Picking a specific hour also previews time-of-day rates that are scheduled but have not started billing yet; those rows are labelled · preview with their start instant. Now only ever shows rates that are billable at this moment.
What this lane charges right now
Priced under the workload and scenario above. The full published schedule below always shows every variant regardless of which scenario is selected.
Where this workload's cost goes
60M input tokens (90% cache hit) and 210K output tokens, at the resolved rate above.
$60.00 + $13.50 + $10.50 = $84.00
How much to trust these numbers
Invite-only Project Glasswing model. Shares Claude Fable 5.1's specifications and $0.25/M cache-read rate.
Anthropic's official Claude pricing and Claude Fable 5.1 model pages, read 2026-09-02: Claude Mythos 5.1 is limited to Project Glasswing participants and shares the published $10/M input, $0.25/M cache read, $50/M output, 1M context and 128K max output. Azure's full Foundry Models Retail Prices API sweep on 2026-09-02 has no Anthropic per-token meter, so this is a Direct row rather than a token-priced Foundry row.
Same-model deployment markup
How much more Microsoft Foundry charges for this exact model, over this Direct rate.
Not available — no Microsoft Foundry listing exists for this exact model in the catalog.
Other lanes within ±25% of this workload's cost
Same provider first, then ranked by cost proximity, for 60M in / 210K out. This is a cost ranking only — never a quality recommendation.
- Claude Fable 5.1ClaudeSame providerDirect API$84.00CHF 67.62$0.00 (0%) vs this lane
- Mistral Medium 3.5MistralFoundry ·Global$91.58CHF 73.72+$7.58 (+9%) vs this lane
- GPT-5.5OpenAI / Azure OpenAIFoundry ·Data Zone$69.63CHF 56.05-$14.37 (-17%) vs this lane
- GPT-5.6 SolOpenAI / Azure OpenAIFoundry ·Data Zone$69.63CHF 56.05-$14.37 (-17%) vs this lane
- Mistral Medium 3.5MistralFoundry ·Data Zone$100.73CHF 81.09+$16.73 (+20%) vs this lane
- GPT-5.5OpenAI / Azure OpenAIFoundry ·Global$63.30CHF 50.96-$20.70 (-25%) vs this lane