AEO Glossary

    Token Limit

    Updated May 19, 20262 min read

    A token limit is the maximum number of tokens a model can read in a single request, prompt plus response combined.

    What is a Token Limit?

    A token limit is the maximum context window an LLM can process at once, measured in tokens (roughly 0.75 words per token). This constraint fundamentally shapes how AI search engines retrieve and synthesize information.

    Token Limits by Platform

    • GPT-4 Turbo: 128,000 tokens (~96,000 words)
    • Claude 3.5 Sonnet: 200,000 tokens (~150,000 words)
    • Gemini 1.5 Pro: 2,000,000 tokens (~1.5 million words)
    • Perplexity Pro: Varies by underlying model

    Why Token Limits Matter

    Token limits directly impact:

    • Source Selection: How many documents can be included in RAG retrieval
    • Attention Quality: Longer contexts dilute attention weights
    • Response Time: Larger contexts require more inference compute
    • Citation Behavior: Models may prioritize early vs. late context differently

    Token Limit Implications for AEO

    Understanding token constraints helps you optimize:

    • Content Length: Concise, high-value content fits more sources in context
    • Information Hierarchy: Place key facts early (before context gets truncated)
    • Source Authority: High-authority sources more likely to be included despite limits
    • Conversational Search: Multi-turn queries consume token budget quickly

    The Token Economy

    As models with larger token limits emerge:

    • More full research becomes possible
    • Long-form content may gain competitive advantage
    • Computation costs increase (affecting platform economics)
    • Grounding strategies must adapt to larger contexts

    Token limits are evolving rapidly, but understanding their current constraints remains critical for effective AEO strategy.

    Related Terms

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