Claude Fable 5 vs o3
Anthropic's Mythos-class flagship for ambitious, long-running professional work.
OpenAI's most powerful reasoning model — top across math, coding, and science.
No captured outputs for these models yet.
Frequently Asked Questions: Claude Fable 5 vs o3▼
Which is better, Claude Fable 5 or o3?
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Based on the Capability Index, Claude Fable 5 scores higher (91.6 vs 79.2). However, "better" depends on your use case — pricing, speed, context window, and specific capability needs all matter.
Which is cheaper, Claude Fable 5 or o3?
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o3 has a lower blended cost. Claude Fable 5: $10.00 input / $50.00 output. o3: $2.00 input / $8.00 output.
Which has a larger context window, Claude Fable 5 or o3?
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Claude Fable 5 has a larger context window: Claude Fable 5 supports 1M tokens vs o3 at 200K tokens.
Do both Claude Fable 5 and o3 support vision?
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Yes, both Claude Fable 5 and o3 support vision/image input.
What are the key differences between Claude Fable 5 and o3?
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Key differences: Claude Fable 5 has a notably higher capability index (12.4 point gap); o3 is significantly cheaper. Compare full specs on this page.
Which model should I choose for my use case?
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If cost is your priority, choose the cheaper option. If you need the highest intelligence for complex tasks, pick the higher-scoring model. For long documents or codebases, choose the larger context window. You can try both Claude Fable 5 and o3 for free on idapt.app to see which performs better for your specific needs.