AI · alternatives · 2026
24 alternatives to OpenAI o1 API
OpenAI's most advanced model, o1 API to third-party devs
OpenAI's o1 API gives developers access to the company's most advanced reasoning model through an API. Designed for complex, multi-step reasoning tasks, it improves upon the earlier o1-preview version with better… 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 API launched in 2024; newer entries below may have overtaken it.
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Open AI o3 API▲141Advanced reasoning models with safety-first innovation.
2024 · openai.com · its alternatives →
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OpenAI o3-mini▲510Pushing the frontier of cost-effective reasoning
2025 · openai.com · its alternatives →
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Advanced Visual Reasoning & Agentic Tool Use
2025 · openai.com · its alternatives →
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gpt-oss-120b and gpt-oss-20b open-weight language models
2025 · openai.com · its alternatives →
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Theneo 3.0▲624The API management platform for humans and agents
2024 · theneo.io · its alternatives →
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Evidently AIfree▲382Open-source evaluations and observability for LLM apps
2024 · evidentlyai.com · its alternatives →
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Agno▲326Build, run, and manage agent platforms. Contribute to agno-agi/agno development by creating an account on GitHub.
2025 · github.com · its alternatives →
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Oxlo.ai▲378Scale across AI models without scaling your bill
Jun 2026 · oxcode.ai · its alternatives →
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2024 best model from xAI, now open source.
2025 · huggingface.co · its alternatives →
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DeepSeek-V3.2▲198Reasoning-first models built for agents
Dec 2025 · huggingface.co · its alternatives →
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O3 alternative
2025 · sota-ai.nfshost.com · its alternatives →
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We built SwiftAI, an open-source Swift library that lets you use Apple’s on-device LLMs when available (Apple opened access in June), and fall back to a cloud model when they aren’t available — all without duplicating code. SwiftAI gives you: - A single, model-agnostic API - An agent/tool loop - Strongly-typed structured outputs - Optional chat state Backstory: We started experimenting with Apple’s local models because they’re free (no API calls), private, and work offline. The problem: not all devices support them (older iPhones, Apple Intelligence disabled, low battery, etc.). That…
2025 · github.com · its alternatives →
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Agnes AI ▲124Hi HN, I'm Daniel, part of the team at Agnes AI, a Singapore-based AI lab. We've been building quietly for a while and I wanted to share what we've made with this community and get honest feedback from people who actually build things. What is Agnes AI? Agnes AI gives you access to three models through a single free API. We have text, image and video models. The API is fully OpenAI-compatible, so you can just swap the base URL to https://apihub.agnes-ai.com/v1 and use your Agnes API key. No other changes needed in your existing code. It is completely free. No need to submit…
2025 · agnes-ai.com · its alternatives →
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Hi everyone, we’re a small team, supported by Mozilla, who are working on re-imagining a UI for training, tuning and testing local LLMs. Everything is open source. If you’ve been training your own LLMs or have always wanted to, we’d love for you to play with the tool and give feedback on what the future development experience for LLM engineering could look like.
2025 · github.com · its alternatives →
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2023 · github.com · its alternatives →
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api2ai parses OpenAPI Spec to generate an agent that can make API calls. For context, I recently need to explore a handful of API suites and thought LLMs can help expedite this process. After some digging, I found OpenAPI Specs are perfect fit for function calling. Based on a text prompt, api2ai can select the right endpoint and properly parse request params and make api calls. It also handles authentication, currently it supports basic auth, api keys, and bearer token schemes. The tool has helped me explore and see APIs in action without a deep dive into the docs or using postman. It’s open…
2023 · github.com · its alternatives →
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Open-source TypeScript framework for AI dev: prompts, evals, tracing, cost tracking, security, and durable execution. Built for Claude Code.
Apr 2026 · output.ai · its alternatives →
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Self-hosted alternative to OpenAI's Responses API compatible with Agents SDK and works with all model providers (Claude/R1/Qwen/Ollama etc) - open-responses/open-responses
2025 · github.com · its alternatives →
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i built an open source version of OpenAI Assistants API it's compatible with any LLM & embeddings model and u can swap it out for OpenAI assistants API with just one line of code. if you want this let me know 👇
2023 · twitter.com · 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 →