ChatGPT vs DeepSeek

ChatGPT is OpenAI's conversational AI assistant and the most widely used AI product in the world. Launched in November 2022, it answers questions, writes and edits text, analyzes files, spreadsheets and images, generates images, searches the web with citations, runs code in a sandbox and produces multi-step research reports with Deep Research. Voice mode supports natural spoken conversation, and apps are available on web, desktop and mobile.

Projects group chats and files around a topic, memory lets ChatGPT remember preferences across conversations, and custom GPTs let anyone package instructions, knowledge and tools for a specific task. Agent mode, introduced in 2025, can operate a virtual browser to complete multi-step tasks such as research, form filling and comparison shopping. The free plan gives limited access to OpenAI's GPT-5 family of models; Plus raises limits and unlocks advanced features, Pro offers the highest limits, and Business (called Team until August 2025) and Enterprise add a shared workspace, admin controls, SSO and a commitment not to train models on business data.

ChatGPT is the default general-purpose assistant for individuals and companies, strong on breadth of features and integrations. Answers can still contain errors, so important facts need checking, and usage limits apply even on paid plans. Claude is often preferred for long documents, writing and coding, Gemini integrates tightly with Google Workspace, and Perplexity focuses on cited search answers.

DeepSeek is a Chinese AI lab and assistant from Hangzhou, founded in 2023 by Liang Wenfeng and funded by the quantitative hedge fund High-Flyer. It became globally known in January 2025 when its open-weight R1 reasoning model matched leading US models at a fraction of the training cost and pushed the DeepSeek app to the top of app store charts.

There are two products. The chat app on web, iOS and Android is free, with thinking and instant modes, web search and file reading. The API is pay-as-you-go: you top up a balance and pay per million tokens, with cache hits billed far below cache misses and off-peak hours at half price. It accepts both OpenAI and Anthropic request formats, so tools like Claude Code can point at it directly. Model weights are published on Hugging Face, so you can also self-host or use cloud providers.

DeepSeek fits developers and cost-sensitive teams that need strong reasoning and coding at very low token prices. Its weak points are data residency and policy: the hosted service stores data in China, and several governments (Italy, South Korea, Australia, Taiwan) have restricted it. ChatGPT and Claude offer richer apps and enterprise controls, while Mistral Le Chat is the EU-hosted option.

The V4 preview in April 2026 brought 1M-token context, and V4.1-Flash-1017 now serves the flash API. For sensitive data, run the open weights on your own infrastructure instead of the hosted app.