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o3-mini vs Claude Fable 5

Detailed pricing comparison and cost analysis.

Updated September 2026

Cost Simulator

o3-mini Cost
$1.98
Claude Fable 5 Cost
$20.00
o3-mini is 90% cheaper
Featureo3-miniClaude Fable 5
ProviderOpenAIAnthropic
Input Price (1M)$1.10$10.00
Output Price (1M)$4.40$50.00
Context Window200,0001,000,000

Verdict

o3-mini costs $1.10 per 1M input tokens and $4.40 per 1M output tokens. Claude Fable 5 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens. o3-mini is 89% cheaper on input tokens than Claude Fable 5. For output tokens, o3-mini is the more affordable option at $4.40/1M vs $50.00.

On context window, Claude Fable 5 supports 1,000,000 tokens — meaning it can fit more conversation history, documents, or code in a single request. This matters for RAG pipelines, long document analysis, and agentic workflows where context builds up over many turns.

When to choose o3-mini

  • ✓ You need the lowest input token cost ($ 1.10/1M)
  • ✓ Your workload is output-heavy — o3-mini generates text cheaper
  • ✓ You are already integrated with OpenAI

When to choose Claude Fable 5

  • ✓ You need a larger context window (1,000,000 tokens)
  • ✓ You are already integrated with Anthropic

Use the calculator above to simulate your specific workload and find the exact break-even point. For most applications, the cheapest model is the one that minimises your total monthly bill given your input-to-output token ratio.

Frequently Asked Questions

Is o3-mini cheaper than Claude Fable 5?

o3-mini is cheaper on input tokens at $1.10/1M vs $10.00/1M for Claude Fable 5 — a 89% saving.

What is the context window of o3-mini vs Claude Fable 5?

o3-mini has a 200,000-token context window. Claude Fable 5 has a 1,000,000-token context window. Claude Fable 5 supports the larger context, suitable for longer documents and agentic workflows.

Which model is better: o3-mini or Claude Fable 5?

The best choice depends on your use case. For cost efficiency on input tokens, o3-mini is the cheaper option. For maximum context length, Claude Fable 5 supports 1,000,000 tokens. Use the comparison table above to find the right fit for your workload.