# DeepSeek

> DeepSeek's chat app is free; its OpenAI-compatible API is pay-per-token (DeepSeek-V4 from $0.14/M input, $0.28/M output) with thinking mode and a 1M-token context.

DeepSeek is a Chinese AI company whose DeepSeek-V3 and R1 models achieved performance matching or exceeding GPT-4o and Claude 3.5 Sonnet at a fraction of the training cost, sending shockwaves through the AI industry. The open-source R1 reasoning model offers transparent chain-of-thought reasoning that rivals OpenAI's o1 series while being freely available for download and deployment. AI developers and researchers worldwide use DeepSeek models as powerful, cost-efficient alternatives to proprietary models, with the open-weight releases enabling fine-tuning, local deployment, and derivative research without any API costs.

## Quick facts

- Categories: Chatbots, Code Assistant, Research
- Pricing: Freemium (free plan + paid tiers) — Consumer chat app: free on web, iOS, and Android. API (pay-per-token, no subscription; charged against a topped-up balance): deepseek-v4-flash — $0.14 per million input tokens (cache miss) or $0.0028 (cache hit), and $0.28 per million output tokens. deepseek-v4-pro — $0.435 per million input tokens (cache miss) or $0.003625 (cache hit), and $0.87 per million output tokens. Context caching delivers roughly a 50x discount on repeated input tokens. The legacy model names deepseek-chat and deepseek-reasoner now route to deepseek-v4-flash (non-thinking and thinking mode respectively).
- Free plan: Yes
- Official site: https://deepseek.com
- Last checked: 2026-10-22

## Key features

- DeepSeek-V4 flagship family with unified thinking and non-thinking modes
- 1M-token context window with up to ~384K-token maximum output
- Free consumer chat app across web, iOS, and Android
- Low-cost, OpenAI-compatible API priced from $0.14 per million input tokens
- Context caching with steep cache-hit discounts (~50x cheaper repeated input)
- Strong reasoning lineage (R1) and coding capability (Coder line)
- Improved agent and tool-use functionality for multi-step tasks
- Open research heritage with publicly documented model releases

## Use cases

- Using powerful AI at lower cost
- Code generation and debugging
- Complex reasoning tasks
- Research on open-source LLMs

## Links

- Nextool.ai page: https://nextool.ai/tools/deepseek-ai/
- Alternatives: https://nextool.ai/alternatives/deepseek-ai/

Source: Nextool.ai (https://nextool.ai/tools/deepseek-ai/). Pricing and features change; confirm on the provider's site before relying on them.