DeepSeek: Free Chat, a Penny-Pincher API, and One Big Catch

The free AI chatbot with serious reasoning: chat free, pay pennies for the API.

Quick answer: DeepSeek is the best free lunch in AI right now.

Our Verdict

DeepSeek is the best free lunch in AI right now. I use the free chat for reasoning tasks I would rather not burn paid credits on, and DeepThink mode often matches outputs I would otherwise get from $20-a-month plans. The trade-offs are real: rate limits with no published quota, and data that lives with a Chinese company. If neither of those bothers you, this is an easy install.

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Pricing shown below is approximate and may have changed — always confirm on the official site.

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🚀 Key Features

Free chatbot at chat.deepseek.com with Instant and Expert answer modes
DeepThink reasoning mode that shows the model's step-by-step thinking
Built-in web search plus file and document uploads on the free tier
Developer API with a 1M-token context window and up to 384K output tokens
API endpoints compatible with OpenAI and Anthropic request formats

💰 Pricing

Plan	Details
Plan	Free Chat (~$0/mo): web and mobile chat with Instant and Expert modes, DeepThink, web search, and file uploads
API Flash (~$0.60/1M output tokens, off	peak): DeepSeek V4.1 Flash with 1M-token context, pay-as-you-go from a prepaid balance
API Pro (~$1.98/1M output tokens, off	peak): V4 Pro with stronger reasoning; peak-hour rates are double, so off-peak costs half

Free chat; API from ~$0.15/1M tokens (approximate) A free tier is available if you want to try before you pay.

👍👎 Pros & Cons

✅ What we like

Completely free chat with no subscription tier, and the reasoning quality is genuinely frontier-class
One of the cheapest frontier APIs anywhere, starting near $0.15 per million input tokens off-peak
OpenAI and Anthropic compatible API, so existing code integrates with barely any changes
Huge 1M-token context window, even for the free chat

🤔 What could be better

No published message quota on the free chat, so busy-hour rate limits arrive with no warning
Run by Hangzhou DeepSeek AI in China, which rules it out for anyone with strict data-residency requirements
API rates double during peak hours, so predictable billing means working around the off-peak window
English-language documentation and support are thinner than what OpenAI or Anthropic offer

❓ Frequently Asked Questions

Is DeepSeek really free?

Yes, the official chat at chat.deepseek.com and the mobile apps are completely free, with no paid subscription tier at all. Only the developer API costs money, billed per million tokens.

Which models power the free chat?

The chat offers Instant and Expert modes plus a DeepThink toggle that shows the model's step-by-step reasoning. Both the Instant and Expert modes draw on DeepSeek's V4 generation of models.

Can I use the DeepSeek API with my existing OpenAI code?

Yes. The API accepts OpenAI Chat Completions and Responses formats as well as the Anthropic Messages format, so most existing code works with little more than a base URL change.

Where does my data go with DeepSeek?

Your data is handled by Hangzhou DeepSeek Artificial Intelligence Co., Ltd., a Chinese company. Treat it like any foreign-hosted service: fine for everyday work, not the place for anything confidential.