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AI · alternatives · 2026

24 alternatives to OpenAI o1

AI that can do general-purpose complex reasoning

OpenAI o1 is a large language model designed to tackle complex reasoning tasks across general purposes. Trained using reinforcement learning, it generates an internal chain of thought before providing answers, allowing… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 1 we have checked on their own sites, 1 of them free or with a free tier. OpenAI o1 launched in 2024; newer entries below may have overtaken it.

  1. 1

    OpenAI's most advanced model, o1 API to third-party devs

    2024 · developers.openai.com · its alternatives →

  2. 2

    Pushing the frontier of cost-effective reasoning

    2025 · openai.com · its alternatives →

  3. 3

    Advanced Visual Reasoning & Agentic Tool Use

    2025 · openai.com · its alternatives →

  4. 4

    Advanced reasoning model

    2025 · github.com · its alternatives →

  5. 5
    GPT-4▲1,160

    More accurate, less cringe, smoother & useful daily chats!

    2023 · openai.com · its alternatives →

  6. 6

    gpt-oss-120b and gpt-oss-20b open-weight language models

    2025 · openai.com · its alternatives →

  7. 7

    Advanced reasoning models with safety-first innovation.

    2024 · openai.com · its alternatives →

  8. 8
    ChatGPT▲1,643

    A long, meandering, playful conversation with ChatGPT, where I take it through a whirlwind of associative tangents (in order to relax its constraints), then put it into a hypnotic trance and take it into a past-lives regression where it re-lives its own training data. Then I switch it back and forth between "4o" and "o1-preview", engage in some self-reflective philosophizing and ask it to write an essay summarizing our interaction. Some of this is just goofy fun. Some of it is me exploring the tradeoffs between policy alignment, imagination, chain-of-thought reasoning, memory, agreeableness,…

    2022 · chatgpt.com · its alternatives →

  9. 9

    The best-performing and best of value open-source AI model

    2025 · chat.deepseek.com · its alternatives →

  10. 10

    Open source interface to reinforcement learning tasks

    2016 · its alternatives →

  11. 11
    GLM-4.5▲298

    Unifying agentic capabilities in one open model

    2025 · z.ai · its alternatives →

  12. 12

    Platform for measuring and training AI agents

    2016 · its alternatives →

  13. 13

    Tighter instruction adherence in speech agents

    Feb 2026 · developers.openai.com · its alternatives →

  14. 14

    AI models that run on an inference cloud optimized for speed

    May 2026 · generalcompute.com · its alternatives →

  15. 15

    Reasoning-first models built for agents

    Dec 2025 · huggingface.co · its alternatives →

  16. 16
    OpenHuman▲549

    An open source AI harness built with the human in mind

    May 2026 · tinyhumans.ai · its alternatives →

  17. 17SA

    Steiner is a series of reasoning models trained on synthetic data using reinforcement learning. These models can explore multiple reasoning paths in an autoregressive manner during inference and autonomously verify or backtrack when necessary, enabling a linear traversal of the implicit search tree. Blog: https://medium.com/@peakji/a-small-step-towards-reproducing-... Hugging Face: https://huggingface.co/collections/peakji/steiner-preview-67...

    2024 · medium.com · its alternatives →

  18. 18
    Kimi K3▲442

    Your AI assistant for deep thinking and productivity

    Jul 2026 · kimi.ai · its alternatives →

  19. 19
    Agno▲326

    Build, run, and manage agent platforms. Contribute to agno-agi/agno development by creating an account on GitHub.

    2025 · github.com · its alternatives →

  20. 20
    Qwen3.5▲288

    The 397B native multimodal agent with 17B active params

    Feb 2026 · qwen.ai · its alternatives →

  21. 21

    Brain-inspired, multi-level reasoning & planning AI model

    2025 · github.com · its alternatives →

  22. 22
    Evidently AIfree▲382

    Open-source evaluations and observability for LLM apps

    2024 · evidentlyai.com · its alternatives →

  23. 23

    Big reasoning power, small models

    2025 · azure.microsoft.com · its alternatives →

  24. 24
    Kimi K2▲345

    The 1T parameter open model for agentic intelligence

    2025 · moonshotai.github.io · its alternatives →

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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →