Together AI is a cloud-based platform that provides infrastructure and services for training, fine-tuning, and running inference on open-source large language models. Founded in 2022, the company aims to make advanced generative AI accessible to developers and enterprises by offering managed compute, optimized model serving, and a suite of development tools.
The platform is built around a high-performance computing stack that leverages NVIDIA GPUs, including H100 and A100 accelerators, to deliver fast and cost-effective inference. Together AI also offers a range of pre-trained open-source models, such as Llama and Mistral, which users can deploy with a simple API call. The company positions itself as an alternative to closed-source providers like OpenAI and Anthropic, emphasizing transparency, customizability, and community-driven innovation.
History and Founding
Together AI was founded in 2022 by a team of researchers and engineers with backgrounds in machine learning and distributed systems. The company emerged from the Stanford AI Lab and was initially incubated as a research project focused on decentralized training of large models. The founding team included Vipul Ved Prakash, Ce Zhang, and Percy Liang, among others.
In 2023, Together AI gained significant attention by releasing open-source models and tools, including the RedPajama dataset and the Together Computer, a distributed training platform. The company raised $102.5 million in a Series A funding round led by Kleiner Perkins in November 2023, bringing its total valuation to over $500 million. By 2024, Together AI had expanded its customer base to include startups and Fortune 500 companies, offering both on-demand and dedicated compute options.
Core Services
Together AI provides three primary services: inference, fine-tuning, and training. The inference service allows developers to deploy open-source models with low latency and high throughput, using an optimized serving engine that supports continuous batching and quantization. The fine-tuning service enables users to adapt base models to specific domains or tasks using their own data, with support for parameter-efficient methods like LoRA.
The training service offers managed clusters for pre-training custom models, with tools for data preparation, job scheduling, and monitoring. Together AI also provides a model library with popular architectures, including transformers and neural networks, and integrates with popular frameworks like PyTorch and Hugging Face. The platform is accessible via a REST API, Python SDK, and a web console, making it suitable for both prototyping and production workloads.
Technology and Infrastructure
Together AI's infrastructure is designed for performance and scalability. The company operates data centers in multiple regions, including the United States and Europe, and uses high-speed networking to interconnect GPU clusters. The serving engine, called Together Inference Engine, incorporates techniques such as tensor parallelism, speculative decoding, and kernel fusion to maximize throughput.
For fine-tuning, Together AI supports both full fine-tuning and efficient methods like LoRA and QLoRA, which reduce memory and compute requirements. The platform also offers a feature called "Together Computer," which allows users to rent idle GPU capacity from a distributed network, similar to CoreWeave but with a focus on open-source models. As of 2024, Together AI has deployed thousands of GPUs and serves billions of tokens daily.
Ecosystem and Partnerships
Together AI has built a vibrant ecosystem around open-source AI. The company collaborates with model developers, including AI21 Labs and Inflection AI, to host their models on the platform. It also partners with cloud providers like Amazon Web Services and Google Cloud to offer integrated solutions, though it maintains its own independent infrastructure.
The company actively contributes to open-source projects, such as the RedPajama dataset, which is a reproduction of the LLaMA training data, and the OpenChatKit, a collection of conversational models. Together AI also sponsors research and hosts community events, including hackathons and meetups, to foster innovation in artificial intelligence. In 2024, the company launched a $10 million fund to support startups building on its platform.
Reception and Impact
Together AI has been recognized as a key player in the democratization of AI, offering an accessible entry point for developers who want to work with open-source models. Industry analysts have praised its performance and cost-efficiency, noting that it often outperforms closed-source alternatives in latency benchmarks. However, some critics have raised concerns about the environmental impact of large-scale GPU computing and the potential for misuse of open-source models.
Despite these challenges, Together AI continues to grow, with a customer base that includes notable companies in finance, healthcare, and technology. The company's commitment to open-source principles has earned it a loyal following among researchers and developers, positioning it as a significant force in the generative AI landscape. As of 2025, Together AI remains a leading provider of cloud inference and fine-tuning services, with plans to expand its offerings to include more specialized tools and enterprise features.
See Also
- Large language model
- Generative AI
- Machine learning
- Cloud computing
References
- Together AI official website and press releases.
- TechCrunch, "Together AI raises $102.5M to build open-source AI models," November 2023.
- VentureBeat, "Together AI launches inference engine for open-source models," March 2024.