whichLlmmodel
Back to Dashboard

AnthropicClaude Fable 5VSGoogleGemini 3.5 Flash

Analysis by:the whichllmmodel Editorial Team|Updated: June 2026

Our Take

We recommend Claude Fable 5 if your workflow requires peak coding capability, or the 5.9x cheaper Gemini 3.5 Flash to optimize your API budget. While both models deliver similar reasoning performance, Claude Fable 5 holds a clear lead in coding. Choose Claude Fable 5 for complex development tasks, or Gemini 3.5 Flash for cost optimization.
▶WHY?
Benchmark Calculations & Evidence:
  • Coding Benchmarks: Both models were evaluated on the SWE-bench Pro benchmark. Claude Fable 5 scored 80.3%, while Gemini 3.5 Flash scored 55.1%.
  • Reasoning Benchmarks: Both models were evaluated on the GPQA Diamond benchmark. Claude Fable 5 scored 94.1%, while Gemini 3.5 Flash scored 92.2%.
  • Cost Efficiency: Gemini 3.5 Flash pricing ($1.5/M input, $9/M output) is 5.9x cheaper than Claude Fable 5 ($10/M input, $50/M output).
    • Was this recommendation helpful?
    Model Specs

    Claude Fable 5

    Website

    Benchmarks & Scores

    Coding (swe-bench-pro)Winner (+25.2%)
    80.3%

    complex codebases, multi-file repositories, and architectural planning

    Reasoning (gpqa-diamond)Winner (+1.9%)
    94.1%

    graduate-level science QA

    Cost & Context

    Cost (per 1M tokens)
    $20.00Input: $10.00 | Output: $50.00
    Context Window
    1.05M tokens
    Model Specs

    Gemini 3.5 Flash

    Website

    Benchmarks & Scores

    Coding (swe-bench-pro)
    55.1%

    complex codebases, multi-file repositories, and architectural planning

    Reasoning (gpqa-diamond)
    92.2%

    graduate-level science QA

    Cost & Context

    Cost (per 1M tokens)5.9x cheaper
    $3.38Input: $1.50 | Output: $9.00
    Context Window
    1.05M tokens
    Read our data collection methodology

    Frequently Asked Questions about Claude Fable 5 vs Gemini 3.5 Flash

    Gemini 3.5 Flash is cheaper than Claude Fable 5. Gemini 3.5 Flash has a blended cost of $3.38/1M tokens, which is about 5.9x cheaper than Claude Fable 5 at $20.00/1M tokens.

    Claude Fable 5 is better for coding tasks on this benchmark. It scores 80.3% on swe-bench-pro (complex codebases, multi-file repositories, and architectural planning) compared to Gemini 3.5 Flash which scores 55.1%.

    Related Matchups

    Explore similar comparisons for Claude Fable 5 and Gemini 3.5 Flash.

    Browse More Comparisons
    AnthropicClaude Fable 5
    VS
    OpenAIGPT-5.5
    Compare Specs
    GoogleGemini 3.5 Flash
    VS
    OpenAIGPT-5.6 Sol
    Compare Specs
    AnthropicClaude Fable 5
    VS
    OpenAIGPT-5.6 Terra
    Compare Specs

    Do you want to find a model for your constraints?

    Use our interactive model finder to filter LLMs by reasoning capability, coding performance, cost, and context length.

    Open Model Finder