Claude Fable 5 vs Gemini 3.5 Flash: Benchmarks, Pricing & Capabilities Compared
TL;DR — Claude Fable 5 wins for reasoning · Gemini 3.5 Flash wins for cost.
Claude Fable 5 Anthropic
- Released
- 2026-06-09
- Context window
- 1M tokens
- Input price
- $10.00 / Mtok
- Output price
- $50.00 / Mtok
Gemini 3.5 Flash Google
- Released
- 2026-05-19
- Context window
- 1M tokens
- Input price
- $1.50 / Mtok
- Output price
- $9.00 / Mtok
Benchmark comparison
| Benchmark | Claude Fable 5 | Gemini 3.5 Flash |
|---|---|---|
| GPQA Diamond | 92.6% ✓ | 82.8% |
| HLE | 53.3% ✓ | 23.1% |
| IF-Bench | 63.5% ✓ | 47.3% |
| LiveCodeBench Reasoning | 70.0% ✓ | 53.3% |
| SciCode | 60.2% ✓ | 48.8% |
| TAU2-bench | 98.5% ✓ | 58.8% |
| TerminalBench-Hard | 62.9% ✓ | 46.2% |
Pricing comparison
| Metric | Claude Fable 5 | Gemini 3.5 Flash |
|---|---|---|
| Input ($/Mtok) | $10.00 | $1.50 |
| Output ($/Mtok) | $50.00 | $9.00 |
| Cached input ($/Mtok) | — | — |
| Cost per 1M-token roundtrip (1M in + 1M out) | $60.00 | $10.50 |
Context window & modalities
| Attribute | Claude Fable 5 | Gemini 3.5 Flash |
|---|---|---|
| Context window | 1M tokens | 1M tokens |
| Input modalities | text, image | text, image, audio, video |
| Output modalities | text | text |
| Knowledge cutoff | — | — |
Verdict by use case
Coding
Insufficient data
Basis: SWE-bench
No shared coding benchmark.
Reasoning
→ Claude Fable 5
Basis: GPQA Diamond
Claude Fable 5 92.6% vs Gemini 3.5 Flash 82.8% on GPQA Diamond.
Math
Insufficient data
Basis: MATH / AIME
No shared math benchmark.
Long context
Tie
Basis: Context window
Claude Fable 5 1M tokens vs Gemini 3.5 Flash 1M tokens.
Cost
→ Gemini 3.5 Flash
Basis: Input $/Mtok
Claude Fable 5 $10/Mtok vs Gemini 3.5 Flash $1.5/Mtok input.
Changelog & releases
Claude Fable 5
Released 2026-06-09
Gemini 3.5 Flash
Released 2026-05-19