DeepSeek

DeepSeek provides a free AI chat app and developer APIs for language, coding, and reasoning tasks. The app suits people who want conversational assistance, while the API supports developers integrating models into their own software. Chat availability and API billing are separate.

Key Highlights

• Web and mobile chat access
• Developer APIs with token-based billing
• deepseek-flash and deepseek-v4-pro API models
• Thinking and non-thinking modes on both API models
• A published 1M-token API context window
• Off-peak API rates at half the peak price

What Makes It Different

DeepSeek combines a chat interface with a usage-based API. The published API model table distinguishes Flash and Pro, rather than separating a general-purpose model from a reasoning-only model. Compare model behavior and cost on your own prompts before choosing one for a workflow.

Features & Capabilities

The chat app supports conversations and document analysis. Developers can use the API for language and coding tasks, with JSON output, function calling, and chat prefix completion on the listed models.

Both API models support thinking and non-thinking modes. Their published context window is 1M tokens, with a maximum output length of 384K tokens. These are API specifications and do not guarantee the same limits or model selection in the chat app. Long context also does not guarantee that every detail will be used correctly.

User Ratings and Testimonials

For a practical evaluation, check the app's current store reviews and test response quality on your own tasks. Assess availability, document handling, and response reliability before relying on it for recurring work. API workloads need their own latency and cost measurements.

Pricing & Value

The chat app offers free access, subject to availability and limits. Developer APIs charge for input and output tokens at model-specific rates, so app access does not include unlimited API usage.

For the published Flash and Pro models, off-peak rates are 50% of peak rates. Peak periods are 01:00-04:00 and 06:00-10:00 UTC on weekdays, excluding Chinese public holidays. Compare the current model rate table and your expected token volume when estimating cost.