Claude Fable 5.1 vs o3

Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.

Claude Fable 5.1 by Anthropic wins on 5 of 7 benchmarks against o3 by OpenAI, which leads on 2. This head-to-head comparison covers coding, math, reasoning, speed, and pricing metrics from our benchmark data.

Category-by-Category Breakdown

Coding: In coding, Claude Fable 5.1 scores 1360 on Design Arena ELO compared to o3's 1074, while Claude Fable 5.1 scores 1322 on Website Arena ELO compared to o3's 1048.

Reasoning: In reasoning, Claude Fable 5.1 scores 90.0% on GPQA Diamond compared to o3's 83.3%.

Context: In context, Claude Fable 5.1 scores 1.0M on Context Length compared to o3's 200K.

Pricing Comparison

Claude Fable 5.1 costs $10.0/1M input tokens and $50.0/1M output tokens, while o3 costs $2.0/1M input and $8.0/1M output. o3 is the more affordable option for API usage.

Verdict

o3 leads across the board in affordability, making it the stronger overall choice in this comparison.

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Claude Fable 5.1 vs o3 — FAQ

Which is better, Claude Fable 5.1 or o3?

Claude Fable 5.1 wins on more benchmarks overall (5 vs 2). However, the best choice depends on your specific needs — each model excels in different areas.

How does Claude Fable 5.1 compare to o3 for coding?

SWE-bench Verified data is not available for both models. Check the detailed comparison charts above for other coding-related metrics.

Is Claude Fable 5.1 cheaper than o3?

Yes, o3 is cheaper. Claude Fable 5.1 costs $10.0/1M input and $50.0/1M output tokens. o3 costs $2.0/1M input and $8.0/1M output tokens.

Which is faster, Claude Fable 5.1 or o3?

Output speed data is not available for both models. Check the speed section of the comparison above for available performance data.

What benchmarks does the Claude Fable 5.1 vs o3 comparison cover?

This comparison covers 7 benchmarks including GPQA Diamond, Input Cost, Output Cost, Context Length, Cached Input Cost, Design Arena ELO, Website Arena ELO. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.