DeepSeek

DeepSeek is a Chinese AI lab that caused a major industry disruption in early 2025 when it released models rivaling GPT-4 quality at a fraction of the cost — and made them open-source. The DeepSeek R1 and V3 models are available completely free via the web interface at chat.deepseek.com with no rate limits, and the model weights can be downloaded and run locally or commercially.

The technical achievements are remarkable: DeepSeek V3 trained for a reported $6 million — compared to hundreds of millions for comparable OpenAI models — using a novel mixture-of-experts architecture that activates only a fraction of parameters per query. On standard benchmarks including MMLU, HumanEval, and MATH, DeepSeek models match or exceed GPT-4o performance, especially in mathematics, coding, and logical reasoning.

The primary concern is data privacy. DeepSeek is operated from China and subject to Chinese data laws, which means conversations may be accessible to Chinese authorities. For personal use, general research, or open-source development this is typically acceptable. For sensitive business content, proprietary code, or confidential data, US-based alternatives like Claude, GPT-4, or a self-hosted local model are strongly recommended.