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ComparisonClaude Opus 5Claude Fable 5Claude Mythos 5

Claude Opus 5 vs Claude Fable 5 vs Claude Mythos 5

Use Claude Opus 5 for difficult everyday coding and enterprise work, Claude Fable 5 when evaluations justify the highest generally available capability and twice the base token price, and Claude Mythos 5 only where approved Project Glasswing access exists.

Comparison dimensions
capability tierpublic availabilityeffort defaultscontext windowmax outputplatform availabilitypricingdeployment governance
Source-backed summary

Anthropic's current model overview and pricing pages define the official capability, access, and price boundaries. Opus 5 and Fable 5 are generally available across major developer platforms, while Mythos 5 is invitation-only. Anthropic's launch performance comparisons are vendor-reported and should be validated on each team's own task harness.

Model-positioning summary

The distinction is three-way: Opus 5 is the advanced everyday model for difficult agentic work, Fable 5 is the highest-capability generally available model, and Mythos 5 is the limited-access invitation tier.

  • Opus 5: $5 input and $25 output per million tokens for complex agentic coding and enterprise work.
  • Fable 5: $10 input and $50 output per million tokens for the most demanding long-running work.
  • Mythos 5: limited access through Project Glasswing, not generally available.
Operational tradeoff

For teams building production coding harnesses, the decision is task success per validated dollar plus access policy, not a single launch benchmark. Start with Opus 5, escalate to Fable 5 only when repeatable evaluations justify the price, and reserve Mythos 5 for approved contexts.

  • Compare pricing, effort profile, latency, refusal behavior, and completion quality against production failure cost.
  • Separate access boundaries from quality claims; Mythos-level quality is only actionable with approved onboarding.
  • Use the same prompts, tools, and validation criteria when comparing Opus 5 and Fable 5.
Access and availability caution

Anthropic clearly states Mythos 5 is not generally available. That means teams should only model it as a candidate where approved pathways exist and internal governance can support the onboarding burden.

Claude Opus 5 vs Claude Fable 5 vs Claude Mythos 5 FAQ

Page-level questions for this comparison.

Which model should I choose first for coding tasks?+

Start with Claude Opus 5 for difficult coding tasks, then test Fable 5 only when the hardest workloads justify its higher price. Reserve Mythos 5 for approved and restricted scenarios.

Is Claude Opus 5 better than Claude Fable 5?+

Not overall. Anthropic positions Fable 5 as its highest-capability generally available model and Opus 5 as the more efficient advanced model. Opus 5 can lead on some vendor-reported evaluations, so use task-specific results and total cost rather than a universal ranking.

Should teams plan for Mythos 5 access in advance?+

Plan Mythos 5 only if your organization has approved access needs and governance controls. Otherwise use Opus 5 or Fable 5 for production routing and treat Mythos 5 as a restricted capability ceiling.