Compare / head-to-head
Claude Fable 5vs
Gemini 3.8 Flash
Claude Fable 5 leads 21 of 27 shared benchmarks. Gemini 3.8 Flash is 13.3x cheaper per token. Gemini 3.8 Flash has the larger context window (1.0M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
21 – 6
Claude Fable 5 leads
Cheaper per token
Gemini 3.8 Flash
13.3x cheaper, input + output
Larger context
Gemini 3.8 Flash
1.0M tokens
Providers
2 providers
Anthropic · Google
Claude Fable 5
Anthropic · released 2026-06-09
textvision
Gemini 3.8 Flash
Google · released 2026-09-02
textvisionaudio
Quality
Benchmark matrix
27 shared · 17 only Claude Fable 5 · 10 only Gemini 3.8 Flash| Benchmark | Claude Fable 5 | Gemini 3.8 Flash | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 27 | ||||
| GPQA Diamond | 85.9% ↗epoch run | 95.3% ↗ | -9.4 pt | Gemini 3.8 Flash |
| LMArena Elo | 1504.3 ↗ | 1494.8 ↗ | +9.5 | Claude Fable 5 |
| APEX-Agents (Mercor) | 63.6% ↗ | 64.3% ↗ | -0.7 pt | Gemini 3.8 Flash |
| Chess Puzzles (Epoch AI run) | 41% ↗epoch run | 61% ↗epoch run | -20 pt | Gemini 3.8 Flash |
| DeepSWE v1.1 (Datacurve) | 69.9% ↗ | 73.8% ↗ | -3.9 pt | Gemini 3.8 Flash |
| FrontierMath Tier 4 v2 (Epoch AI run) | 90.2% ↗epoch run | 22% ↗epoch run | +68.2 pt | Claude Fable 5 |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 87% ↗epoch run | 68.4% ↗epoch run | +18.6 pt | Claude Fable 5 |
| FrontierSWE V2 (Proximal Labs) | 47% ↗ | 19.6% ↗ | +27.4 pt | Claude Fable 5 |
| Furniture Assembly (Epoch AI run) | 35.8% ↗epoch run | 31.7% ↗epoch run | +4.1 pt | Claude Fable 5 |
| LiveBench Agentic Coding (LiveBench) | 62.2% ↗ | 54.2% ↗ | +8 pt | Claude Fable 5 |
| LiveBench Coding (LiveBench) | 86% ↗ | 72.5% ↗ | +13.5 pt | Claude Fable 5 |
| LiveBench Data Analysis (LiveBench) | 80.5% ↗ | 54% ↗ | +26.5 pt | Claude Fable 5 |
| LiveBench Instruction Following (LiveBench) | 75.8% ↗ | 81.4% ↗ | -5.6 pt | Gemini 3.8 Flash |
| LiveBench Language (LiveBench) | 90.7% ↗ | 87.8% ↗ | +2.9 pt | Claude Fable 5 |
| LiveBench Mathematics (LiveBench) | 96% ↗ | 91.6% ↗ | +4.4 pt | Claude Fable 5 |
| LiveBench Reasoning (LiveBench) | 89.7% ↗ | 89.3% ↗ | +0.4 pt | Claude Fable 5 |
| LMArena Agent (LMArena) | 0.0821 ↗ | 0.0297 ↗ | +0.1 | Claude Fable 5 |
| LMArena Vision (LMArena) | 1308.8 ↗ | 1290.3 ↗ | +18.5 | Claude Fable 5 |
| LMArena WebDev (LMArena) | 1625.3 ↗ | 1582.7 ↗ | +42.6 | Claude Fable 5 |
| Mystery Game Puzzles (Epoch AI run) | 52% ↗epoch run | 47% ↗epoch run | +5 pt | Claude Fable 5 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 100% ↗epoch run | 98.9% ↗epoch run | +1.1 pt | Claude Fable 5 |
| SAGE (Vals AI) | 51.9% ↗ | 35.1% ↗ | +16.8 pt | Claude Fable 5 |
| SimpleBench (SimpleBench) | 81.9% ↗ | 82.4% ↗ | -0.5 pt | Gemini 3.8 Flash |
| SimpleQA Verified | 70.7% ↗epoch run | 69.7% ↗epoch run | +1 pt | Claude Fable 5 |
| Terminal-Bench 4.0 (Vals AI) | 41.4% ↗ | 19.2% ↗ | +22.2 pt | Claude Fable 5 |
| Vending-Bench 2 (Andon Labs) | 5680.26 ↗ | 5093.79 ↗ | +586.5 | Claude Fable 5 |
| WeirdML (Håvard Tveit Ihle) | 91.9% ↗ | 84.8% ↗ | +7.1 pt | Claude Fable 5 |
| Only Claude Fable 5 reports · 17 | ||||
| SWE-bench Verified | 95% ↗ | not reported | — | — |
| AutomationBench | 17.4% ↗ | not reported | — | — |
| Blueprint-Bench 2 | 38.6% ↗ | not reported | — | — |
| CursorBench | 72.9% ↗ | not reported | — | — |
| EBR-bench (Epoch AI run) | 39.5% ↗epoch run | not reported | — | — |
| FrontierCode (Diamond) | 29.3% ↗ | not reported | — | — |
| GDP.pdf | 29.8% ↗ | not reported | — | — |
| GSO Opt@1 (GSO) | 76.5% ↗ | not reported | — | — |
| Legal Agent Benchmark (Harvey's Held-Out Set) | 13.3% ↗ | not reported | — | — |
| MirrorCode (Epoch AI run) | 63.9% ↗epoch run | not reported | — | — |
| OfficeQA Pro | 57.9% ↗ | not reported | — | — |
| OSWorld-Verified | 85% ↗ | not reported | — | — |
| OSWorld-Verified (XLANG) | 86% ↗ | not reported | — | — |
| SWE-Bench Pro | 80% ↗ | not reported | — | — |
| SWE-rebench 2026-05-15 to 2026-07-01 (Nebius) | 64.5% ↗ | not reported | — | — |
| tau2-bench Banking Knowledge (Sierra) | 39.7% ↗ | not reported | — | — |
| Terminal-Bench 2.1 | 84.3% ↗ | not reported | — | — |
| Only Gemini 3.8 Flash reports · 10 | ||||
| CharXiv Reasoning (no tools) | not reported | 86.2% ↗ | — | — |
| DeepSWE v1.1 | not reported | 73.7% ↗ | — | — |
| GDPVal-AA v2 | not reported | 1545 ↗ | — | — |
| Harvey's Legal Agent Benchmark | not reported | 10% ↗ | — | — |
| HLE-Verified | not reported | 54.9% ↗ | — | — |
| LABBench2 | not reported | 86.2% ↗ | — | — |
| OSWorld-2.0 | not reported | 59% ↗ | — | — |
| Terminal-bench 2.1 | not reported | 89.4% ↗ | — | — |
| Terminal-bench 4.0 | not reported | 19.1% ↗ | — | — |
| Vals Finance Agent v2 | not reported | 61.4% ↗ | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Fable 5 minus Gemini 3.8 Flash in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | Claude Fable 5 | Gemini 3.8 Flash | Edge |
|---|---|---|---|
| Context window | 1M tokens | 1.0M tokens | Gemini 3.8 Flash |
| Max output | 128K tokens | 66K tokens | Claude Fable 5 |
| Input price / 1M | $10 ↗ | $0.75 ↗ | Gemini 3.8 Flash |
| Output price / 1M | $50 ↗ | $3.75 ↗ | Gemini 3.8 Flash |
| Cached input / 1M | $1 ↗ | $0.075 ↗ | Gemini 3.8 Flash |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $60 | $4.5 | Gemini 3.8 Flash |
| Modalities | text · vision | text · vision · audio | Gemini 3.8 Flash |
| Released | 2026-06-09 | 2026-09-02 | — |
| Cited benchmark scores | 44 | 43 | — |
Reliability
Provider status
Live from /statusMore matchups
Claude Fable 5 vs …
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Gemini 3.8 Flash vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run Claude Fable 5 and Gemini 3.8 Flash on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.