Model comparison
Claude Fable 5 vs o3-mini
Head-to-head evidence from 6 shared benchmark results across 3 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Fable 5 #2 (Supported); o3-mini #136 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Fable 5 and o3-mini share 6 comparable benchmark results. 1 of 8 categories are comparable. 28 results are unique to Claude Fable 5; 4 to o3-mini.
Updated July 23, 2026- Shared results
- 6
- Claude Fable 5 only
- 28
- o3-mini only
- 4
- Comparable categories
- 1 / 8
Pick Claude Fable 5 if you want the stronger benchmark profile. o3-mini only becomes the better choice if you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 6 shared benchmark results across 3 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Fable 5 is clearly ahead on the BenchAlign aggregate, 83.68 to 47.41. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Fable 5's sharpest advantage is in coding, where it averages 89.2 against 49.3. The single biggest benchmark swing on the page is SWE-bench Verified, 95% to 49.3%.
Claude Fable 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $1.10 input / $4.40 output per 1M tokens for o3-mini. That is roughly 11.4x on output cost alone. Claude Fable 5 gives you the larger context window at 1M+, compared with 200K for o3-mini.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Claude Fable 5 | Δ | o3-mini |
|---|---|---|---|
| Coding | Claude Fable 589.2 | Margin← 39.9 | o3-mini49.3 |
| Agentic | Claude Fable 584.6 | MarginNo overlap | o3-miniNot measured |
| Knowledge | Claude Fable 5Not measured | MarginNo overlap | o3-mini77.2 |
| Multimodal | Claude Fable 557.9 | MarginNo overlap | o3-miniNot measured |
| Inst. Following | Claude Fable 5Not measured | MarginNo overlap | o3-mini93.9 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Verified
CodingA 95%B 49.3%Winner: Claude Fable 5Δ 45.7SWE-bench Verified: Claude Fable 5 scored 95%; o3-mini scored 49.3%. Claude Fable 5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Fable 5 | o3-mini | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Fable 5$10 input / $50 output | o3-mini$1.1 input / $4.4 output | o3-mini has the lower combined listed price. |
| Generation speedtokens per second | Claude Fable 5Not available | o3-mini160 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Fable 5Not available | o3-mini7.12 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Fable 51M+ | o3-mini200K | Claude Fable 5 lists the larger context window. |
Benchmark Deep Dive
Agentic13 benchmarks
| Benchmark | Claude Fable 5 | o3-mini | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 84.3% | — | Not comparable |
| OSWorld-VerifiedSource | 85% | — | Not comparable |
| GDPval-AASource | 1748 | — | Not comparable |
| AA Agentic IndexSource | 52.8% | — | Not comparable |
| τ²-bench resultsSource | 98.5% | 28.7% | Claude Fable 5 leads |
| GDPval-AASource | 62.4% | — | Not comparable |
| AA BriefcaseSource | 1574 | — | Not comparable |
| AA AutomationBenchSource | 48.6% | — | Not comparable |
| AA EnterpriseOps-GymSource | 51.1% | — | Not comparable |
| AA Harvey LABSource | 93.6% | — | Not comparable |
| AA Tau3 BankingSource | 26.8% | — | Not comparable |
| terminalBenchHardSource | 62.9% | — | Not comparable |
| aaTerminalBench21Source | 84.6% | — | Not comparable |
CodingClaude Fable 5 wins9 benchmarks
| Benchmark | Claude Fable 5 | o3-mini | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95% | 49.3% | Claude Fable 5 leads |
| SWE-bench ProSource | 80% | — | Not comparable |
| FrontierCode 1.1 MainSource | 53.5% | — | Not comparable |
| Terminal-Bench 2.0Source | 84.3% | — | Not comparable |
| cursorBench31Source | 70.6% | — | Not comparable |
| cursorBench32Source | 70.5% | — | Not comparable |
| VulcanBench v3Source | 87.0% | — | Not comparable |
| AA Coding IndexSource | 76.5% | — | Not comparable |
| AA-SciCodeSource | 60.2% | 39.9% | Claude Fable 5 leads |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Claude Fable 5 | o3-mini | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 59.9% | 19.0% | Claude Fable 5 leads |
| AA-GPQA DiamondSource | 92.6% | 74.8% | Claude Fable 5 leads |
| AA-HLESource | 53.3% | 8.7% | Claude Fable 5 leads |
| AA-Omniscience IndexSource | 40.2% | — | Not comparable |
| AA-Omniscience AccuracySource | 61.4% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 54.9% | — | Not comparable |
| MMLUSource | — | 86.9% | Not comparable |
| GPQASource | — | 77.2% | Not comparable |
Math1 benchmarks
| Benchmark | Claude Fable 5 | o3-mini | Result |
|---|---|---|---|
| AIME 2024Source | — | 87.3% | Not comparable |
Multimodal3 benchmarks
Frequently Asked Questions (2)
Which is better, Claude Fable 5 or o3-mini?
Claude Fable 5 is ahead on BenchLM's BenchAlign leaderboard, 83.68 to 47.41. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 95% and 49.3%.
Which is better for coding, Claude Fable 5 or o3-mini?
Claude Fable 5 has the edge for coding in this comparison, averaging 89.2 versus 49.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
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