DeepSeek is a Chinese AI research lab that develops high-performance open-source language models with a focus on reasoning quality, mathematical accuracy, and cost-efficient training. DeepSeek gained global attention by demonstrating that frontier-level AI performance can be achieved at a fraction of the cost of competitors, challenging assumptions about the capital requirements for building leading AI systems. The DeepSeek chat assistant provides free access to their latest models through a web interface and mobile apps.
Current DeepSeek API docs foreground V4 Flash and V4 Pro, with thinking and non-thinking modes, OpenAI-compatible and Anthropic-compatible endpoints, JSON output, tool calls, 1M context, and up to 384K max output. Older V3/R1-era names still matter historically and in open-model discussions, but evergreen buyer copy should verify the exact model, alias, and deprecation timeline before relying on them.
DeepSeek appeals to developers, researchers, and organizations seeking powerful open-source models that can be self-hosted, fine-tuned, and deployed without vendor lock-in. The models are available through the DeepSeek API with competitive pricing, and are also hosted on major inference platforms including Together AI, Fireworks AI, and AWS Bedrock. DeepSeek's open-weight approach has made it a popular choice for academic research, custom AI applications, and cost-conscious deployments. It competes directly with Llama, Mistral, and Qwen in the open-source model space, while its chat product rivals Claude and ChatGPT for everyday use.
