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Model guide · updated 2026

Fastest AI models

When latency matters — real-time chat, agent loops, high-volume pipelines — raw output speed wins. These models are ranked by measured output throughput in tokens per second.

  1. 1

    GPT OSS 120B Fast

    OpenAITop pick

    Agentic workflows and multi-tool automation requiring reliable function calling and chain-of-thought reasoning

    1971
    Tokens / sec
  2. 2

    Gemini 3.1 Flash-Lite

    Google

    High-volume translation of chat messages

    318.5
    Tokens / sec
  3. 3

    Gemini 3.1 Flash-Lite Preview

    Google

    High-volume content classification and moderation

    316.1
    Tokens / sec
  4. 4

    GPT OSS 120b

    OpenAI

    Agentic coding and engineering workflows

    304.6
    Tokens / sec
  5. 5

    MiniMax M2.5

    MiniMax

    High-volume software engineering and code generation across Web

    241
    Tokens / sec
  6. 6

    GPT OSS 20b

    OpenAI

    Mathematical and technical reasoning

    225.3
    Tokens / sec
  7. 7

    Gemini 2.5 Flash-Lite

    Google

    High-volume content classification

    224.1
    Tokens / sec
  8. 8

    o3 mini

    OpenAI

    Math and STEM problem-solving

    219.6
    Tokens / sec

Ranked by measured output speed (tokens per second) from Artificial Analysis, fastest first.

Compare the top picks →All models

Frequently asked questions

Two things: output speed (tokens generated per second) and time-to-first-token (how quickly the first word appears). This list ranks by output speed; reasoning models can be fast at generating but slow to start because they "think" first.

Often the fastest models are smaller or "flash"/"mini" variants tuned for throughput, so they trade some peak reasoning for speed. For chat, drafting and high-volume tasks that trade-off is usually worth it.

Agentic workflows make many model calls in a loop, so per-call latency compounds. A faster model can cut an agent run from minutes to seconds.