Model comparison
Claude Fable 5 vs Gemini 3.1 Flash-Lite
Head-to-head evidence from 15 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Fable 5 #2 (Supported); Gemini 3.1 Flash-Lite #111 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Fable 5 and Gemini 3.1 Flash-Lite share 15 comparable benchmark results. 1 of 8 categories are comparable. 19 results are unique to Claude Fable 5; 5 to Gemini 3.1 Flash-Lite.
Updated July 23, 2026- Shared results
- 15
- Claude Fable 5 only
- 19
- Gemini 3.1 Flash-Lite only
- 5
- Comparable categories
- 1 / 8
Pick Claude Fable 5 if you want the stronger benchmark profile. Gemini 3.1 Flash-Lite only becomes the better choice if multimodal & grounded is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 15 shared benchmark results across 5 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 50.83. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Fable 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $0.25 input / $1.50 output per 1M tokens for Gemini 3.1 Flash-Lite. That is roughly 33.3x on output cost alone. Claude Fable 5 is the reasoning model in the pair, while Gemini 3.1 Flash-Lite is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Claude Fable 5 gives you the larger context window at 1M+, compared with 1M for Gemini 3.1 Flash-Lite.
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 | Gemini 3.1 Flash-Lite |
|---|---|---|---|
| Multimodal | Claude Fable 557.9 | Margin→ 15.3 | Gemini 3.1 Flash-Lite73.2 |
| Agentic | Claude Fable 584.6 | MarginNo overlap | Gemini 3.1 Flash-LiteNot measured |
| Coding | Claude Fable 589.2 | MarginNo overlap | Gemini 3.1 Flash-LiteNot measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Fable 5 | Gemini 3.1 Flash-Lite | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Fable 5$10 input / $50 output | Gemini 3.1 Flash-Lite$0.25 input / $1.5 output | Gemini 3.1 Flash-Lite has the lower combined listed price. |
| Generation speedtokens per second | Claude Fable 5Not available | Gemini 3.1 Flash-Lite205 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Fable 5Not available | Gemini 3.1 Flash-Lite7.50 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Fable 51M+ | Gemini 3.1 Flash-Lite1M | Claude Fable 5 lists the larger context window. |
Benchmark Deep Dive
Agentic15 benchmarks
| Benchmark | Claude Fable 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 84.3% | — | Not comparable |
| OSWorld-VerifiedSource | 85% | — | Not comparable |
| GDPval-AASource | 1748 | 642 | Claude Fable 5 leads |
| AA Agentic IndexSource | 52.8% | 6.2% | Claude Fable 5 leads |
| τ²-bench resultsSource | 98.5% | 31.3% | Claude Fable 5 leads |
| GDPval-AASource | 62.4% | 7.1% | Claude Fable 5 leads |
| 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 |
| APEX-Agents-AASource | — | 12.2% | Not comparable |
| Gert LabsSource | — | 38.46% | Not comparable |
Coding10 benchmarks
| Benchmark | Claude Fable 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95% | — | Not comparable |
| 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% | 34.7% | Claude Fable 5 leads |
| AA-SciCodeSource | 60.2% | 41.9% | Claude Fable 5 leads |
| Vibe Code BenchSource | — | 0.00% | Not comparable |
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Claude Fable 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 59.9% | 25.0% | Claude Fable 5 leads |
| AA-GPQA DiamondSource | 92.6% | 82.2% | Claude Fable 5 leads |
| AA-HLESource | 53.3% | 16.2% | Claude Fable 5 leads |
| AA-Omniscience IndexSource | 40.2% | -15.5% | Claude Fable 5 leads |
| AA-Omniscience AccuracySource | 61.4% | 36.4% | Claude Fable 5 leads |
| AA-Omniscience Hallucination RateSource | 54.9% | 81.6% | Claude Fable 5 leads |
MultimodalGemini 3.1 Flash-Lite wins5 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Fable 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| AA-IFBenchSource | 63.5% | 77.2% | Gemini 3.1 Flash-Lite leads |
Frequently Asked Questions (2)
Which is better, Claude Fable 5 or Gemini 3.1 Flash-Lite?
Claude Fable 5 is ahead on BenchLM's BenchAlign leaderboard, 83.68 to 50.83.
Which is better for multimodal and grounded tasks, Claude Fable 5 or Gemini 3.1 Flash-Lite?
Gemini 3.1 Flash-Lite has the edge for multimodal and grounded tasks in this comparison, averaging 73.2 versus 57.9. Claude Fable 5 stays close enough that the answer can still flip depending on your workload.
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