Model Comparison
Claude Fable 5 vs Gemini 3.5 FlashWhich is better in 2026?
Claude Fable 5 significantly outperforms across most benchmarks. Gemini 3.5 Flash is 5.9x cheaper per token.
Verdict: Claude Fable 5 vs Gemini 3.5 Flash — which is better?
Claude Fable 5 (by Anthropic) and Gemini 3.5 Flash (by Google) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
Claude Fable 5 outperforms in 7 benchmarks (Blueprint-Bench 2, GDPval-AA, Humanity's Last Exam, Legal Agent Benchmark, LiveBench, OSWorld-Verified, SWE-Bench Pro), while Gemini 3.5 Flash is better at 1 benchmark (Finance Agent v2). Claude Fable 5 significantly outperforms across most benchmarks.
On price, Gemini 3.5 Flash is roughly 5.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 3.5 Flash also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.
Choose Claude Fable 5 if…
- you want the strongest raw capability — it leads on 7 of 8 shared benchmarks
- you want the most recent training data — it shipped Jun 2026
Choose Gemini 3.5 Flash if…
- cost matters — it's about 5.9x cheaper per token
- you process long inputs — it offers a 1,048,576 token context window
Performance Benchmarks
Comparative analysis across standard metrics
Claude Fable 5 outperforms in 7 benchmarks (Blueprint-Bench 2, GDPval-AA, Humanity's Last Exam, Legal Agent Benchmark, LiveBench, OSWorld-Verified, SWE-Bench Pro), while Gemini 3.5 Flash is better at 1 benchmark (Finance Agent v2).
Claude Fable 5 significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Fable 5 ($10.00/1M tokens) is 6.7x more expensive than Gemini 3.5 Flash ($1.50/1M tokens).
For output processing, Claude Fable 5 ($50.00/1M tokens) is 5.6x more expensive than Gemini 3.5 Flash ($9.00/1M tokens).
In conclusion, Claude Fable 5 is more expensive than Gemini 3.5 Flash.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 3.5 Flash accepts 1,048,576 input tokens compared to Claude Fable 5's 1,000,000 tokens. Claude Fable 5 can generate longer responses up to 128,000 tokens, while Gemini 3.5 Flash is limited to 65,536 tokens.
Input Capabilities
Supported data types and modalities
Both Claude Fable 5 and Gemini 3.5 Flash support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Fable 5
Gemini 3.5 Flash
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude Fable 5 was released on 2026-06-09, while Gemini 3.5 Flash was released on 2026-05-19.
Claude Fable 5 is 1 month newer than Gemini 3.5 Flash.
Jun 9, 2026
1 months ago
3w newerMay 19, 2026
1 months ago
Knowledge Cutoff
When training data ends
Gemini 3.5 Flash has a documented knowledge cutoff of 2026-01-31, while Claude Fable 5's cutoff date is not specified.
We can confirm Gemini 3.5 Flash's training data extends to 2026-01-31, but cannot make a direct comparison without Claude Fable 5's cutoff date.
—
Jan 2026
Provider Availability
Claude Fable 5 is available from Anthropic. Gemini 3.5 Flash is available from Google.
Claude Fable 5
Gemini 3.5 Flash
Outputs Comparison
Key Takeaways
Claude Fable 5
View detailsAnthropic
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against Claude Fable 5 and Gemini 3.5 Flash side-by-side, then vote on the output you prefer.
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FAQ
Common questions about Claude Fable 5 vs Gemini 3.5 Flash.