DeepSeek

DeepSeek

Provider

DeepSeek

Price

$0 (free)

Platforms

Web, iOS, Android

Launched

Jan 2025

Updated June 2026

DeepSeek is a free AI chat app from the Chinese lab DeepSeek, and it is the only way most people get frontier-class reasoning at no cost with no paid tier at all. The app runs DeepSeek V4 with a one-million-token context window and a DeepThink mode that shows its working on maths, logic and code. The single biggest caveat is data residency: prompts and responses are stored on servers in China, which is why Italy, Australia, South Korea and others have restricted the app — so it is a strong pick for everyday and budget use, and the wrong pick for sensitive or regulated data. For privacy-sensitive work, run the same MIT-licensed model yourself or use Le Chat instead.

DeepSeek broke into global view in January 2025, when its app became the most-downloaded free app on the US App Store and topped the charts across dozens of countries, forcing a wider reckoning over how cheaply a capable model could be built and served. Eighteen months on it is a permanent fixture: by January 2026 the app reached about 131.5 million monthly active users, second only to ChatGPT among AI assistants. This guide covers the free consumer app across web and mobile — what it does, what powers it, and the privacy trade-offs that decide whether you should use it.

Quick stats

Pricing breakdown

DeepSeek’s pricing is the simplest in this category: the consumer app is free, with no Plus, Pro or Max tier to upsell. There is one experience, and everyone gets it.

Free — $0

The free app includes the full feature set with no paywalled models:

• DeepSeek V4 — the current flagship model, the same one available through the paid API
• DeepThink reasoning mode — toggle on chain-of-thought reasoning (R-series) for harder problems
• Web search — an optional toggle that pulls current information into an answer
• File uploads — PDF, DOCX and TXT for summarisation and contextual Q&A
• Image understanding — upload an image for analysis (not image generation)
• Voice input — dictation on the mobile apps
• 1M-token context — long documents and conversations in a single thread
• History sync — conversations carry across web and mobile

Limitations: no image or video generation, no conversational voice mode, no agent or task automation, and no enterprise data-protection tier. The trade-off for “free and unlimited” is that consumer data is processed in China (see Privacy and data handling).

API — pay-as-you-go (separate from the app)

The app is free, but developers who want the same models programmatically pay by the token. DeepSeek’s API is among the cheapest from any major lab — see the DeepSeek V4 model page for current per-token rates and the DeepSeek provider page for the full lineup. There is no consumer subscription that sits between the free app and the API.

Self-hosting — free under MIT

Because DeepSeek V4 ships as open weights under the MIT licence, the same model can be downloaded from Hugging Face and run on your own hardware or a third-party cloud. This is the route organisations use to get DeepSeek’s capability without sending data to China — the capability is identical; only where it runs changes.

Models powering DeepSeek

In the app you talk to a single model by default and flip on DeepThink for reasoning. Here is what sits underneath. For full benchmarks and pricing, each model has its own page.

DeepSeek V4 (April 2026)

DeepSeek V4 is the current model, released as a preview on 24 April 2026 across web, app and API:

• Two Mixture-of-Experts sizes — V4-Pro (1.6 trillion parameters, 49 billion active) and V4-Flash (284 billion, 13 billion active), per independent analysis
• 1M-token context window — entire codebases and long document sets in one pass
• 80.6% on SWE-bench Verified (vendor-reported) — within a fraction of a point of last year’s proprietary leaders, and the top open-weight coding score on the site’s best AI models board
• Open weights (MIT licence) — free to download and self-host

Available to: all app users by default, at no cost.

DeepSeek R-series — DeepThink (January 2025 onward)

DeepThink is powered by DeepSeek’s reasoning line, DeepSeek R1 and its successor R2. The original R1 launched on 20 January 2025 and was the model that made DeepSeek a global story:

• Visible chain-of-thought — the model shows its reasoning steps before answering
• Stronger on maths, logic and multi-step code — at the cost of slower responses (often 15–60 seconds)
• Open weights — the R-series is also MIT-licensed and self-hostable

Available to: all app users via the DeepThink toggle.

DeepSeek V3.2 (legacy, still in transition)

DeepSeek V3.2 powered the app through late 2025 and early 2026 and was the general-purpose model before V4. Vendor documentation listed the app as running “V3.2 and R1” as recently as January 2026. V4 arrived as a preview on 24 April 2026 and is the headline model, but DeepSeek has set 24 July 2026 as the retirement date for the legacy V3.2-backed API names — so V3.2 and R1 still run in parallel during the transition. Where you see references to V3 or V3.2, they describe the previous generation.

Features deep dive

DeepThink — visible reasoning

DeepThink is DeepSeek’s headline feature and the reason the app punches above its price. Toggling it on switches from a fast general answer to the reasoning line, which works through a problem step by step and shows that working. It is materially better on competition maths, logic puzzles and multi-step coding, and weaker on speed — responses commonly take 15–60 seconds. It is the closest free equivalent to the paid reasoning modes in ChatGPT and Gemini.

Web search

DeepSeek includes an optional Search toggle that queries the web before answering, so the model can cite current information rather than relying on its training data alone. It is off by default and switched on per query, similar to Claude’s selective approach rather than ChatGPT’s always-on browsing. Available to all users at no cost.

File uploads and image understanding

The app accepts PDF, DOCX and TXT uploads for summarisation and contextual question-answering, and can analyse uploaded images (charts, screenshots, photos). This is vision input only — DeepSeek reads images, it does not generate them.

Voice input

The iOS and Android apps support voice input (dictation) so you can speak a prompt instead of typing. This is speech-to-text, not a conversational voice mode: DeepSeek does not hold a spoken back-and-forth the way ChatGPT’s real-time voice does.

Long context

Every conversation runs on a 1M-token context window, so entire contracts, papers or codebases fit in a single thread without the model losing the thread. This matches the long-context windows on flagship models from Anthropic and Google and is unusually generous for a free app.

What DeepSeek does not do

DeepSeek is deliberately narrow. There is no image generation, no video generation, no conversational voice mode, no custom bots or GPT-style store, no projects or canvas workspace, and no agent or scheduled-task automation. It is a fast, free reasoning chat — not an all-in-one multimedia suite.

Strengths

It is genuinely free. DeepSeek gives unlimited access to a frontier-class model with no paid tier and no obvious message cap — the most capable free chat experience available, alongside Google’s free Gemini tier.

Reasoning quality. DeepThink produces strong, visible step-by-step reasoning on maths, logic and code, and DeepSeek V4 scores 80.6% on SWE-bench Verified (vendor-reported), close to last year’s proprietary leaders.

Open weights. Both V4 and the R-series ship under the MIT licence, so the exact capability in the app can be self-hosted — a privacy and control escape hatch no closed app offers.

Long context. A 1M-token window handles whole documents and codebases in one pass, free.

Reach and momentum. At roughly 131.5 million monthly active users in January 2026, DeepSeek is the second most-used AI assistant after ChatGPT, with an active model-release cadence behind it.

Limitations

Data residency in China. Consumer prompts and responses are stored on servers in the People’s Republic of China, which is the central reason to keep sensitive, confidential or regulated data out of the app.

Government restrictions. Italy, Australia, South Korea, Taiwan, India, the Czech Republic and a number of US states and agencies have banned or restricted the app, and Germany has asked Apple and Google to delist it (Al Jazeera). For many organisations the app is simply off the table.

No media generation. No images, no video. If you need DALL-E or Veo-style output, DeepSeek is not the tool.

Voice is input only. Dictation, not conversation — ChatGPT and Gemini are far ahead on spoken interaction.

Thin feature set. No memory across chats, no projects, no connectors, no agent mode. It is a capable chat box, not a work platform.

Slower in DeepThink. The reasoning mode that makes DeepSeek good is also slow, with answers often taking 15–60 seconds.

Who should use DeepSeek?

Great for:

• Students and budget users — frontier-class reasoning, maths and code for free
• Anyone doing maths, logic or step-by-step problem solving — DeepThink is the draw
• Developers evaluating an open-weight model — try it in the app, then self-host V4 under MIT
• Non-sensitive everyday tasks — drafting, explaining, summarising public information

Look elsewhere if:

• You handle sensitive, confidential or regulated data — China data residency rules it out; use Le Chat (EU/GDPR) or a self-hosted open model instead
• You are in government or a restricted jurisdiction — the app is banned or restricted in several countries
• You need image or video generation — use ChatGPT or Gemini
• You want voice-first interaction — ChatGPT’s real-time voice is far ahead

Historical timeline

Privacy and data handling

Privacy is the decisive issue with DeepSeek, and it is worth being precise about.

Where your data goes

DeepSeek’s privacy policy states that user data is stored on servers located in the People’s Republic of China. That includes prompts, responses and account and device information. Under China’s 2017 National Intelligence Law, organisations can be compelled to assist state intelligence work, which is the basis for most of the regulatory concern. Security researchers also reported code in early versions of the app that communicated with infrastructure tied to China Mobile; DeepSeek has not detailed those data flows publicly. Treat anything you type into the consumer app as leaving your control.

Government restrictions

How to use DeepSeek privately

The clean answer is don’t send sensitive data to the hosted app. Two routes preserve DeepSeek’s capability without the China data path: self-host the MIT-licensed V4 weights on your own infrastructure, or run them through a non-Chinese cloud provider that hosts open weights. For a managed app with strong privacy guarantees, Le Chat from Mistral is EU-based and built around GDPR. See the privacy section of the best AI apps ranking for the full picture.

DeepSeek vs alternatives

Quick comparison

Where DeepSeek wins

• Price — frontier-class reasoning with no paid tier at all
• Open weights — the same model is self-hostable under MIT, which closed apps cannot match
• Reasoning value — DeepThink rivals paid reasoning modes for free

Where competitors win

• ChatGPT — image and video generation, real-time voice, memory, custom GPTs, US data handling and a far broader ecosystem
• Qwen — free multimodal and multilingual chat with image generation, though also China-hosted
• Kimi — very long context and strong agentic features, also China-hosted
• Le Chat — EU data residency and GDPR alignment for privacy-sensitive use

Getting started

Web

1. Go to chat.deepseek.com
2. Sign in (email, Google or Apple)
3. Start chatting — toggle DeepThink for reasoning and Search for current information

Mobile

• iOS: Download from the App Store
• Android: Download from Google Play (availability varies by country)

Tips for new users

Use DeepThink for hard problems only. It is slower; leave it off for quick lookups and switch it on for maths, logic and multi-step code.

Toggle Search for anything time-sensitive. DeepSeek does not browse by default, so turn on Search for news, prices or recent events.

Keep sensitive data out. Do not paste confidential, personal or regulated information into the hosted app — assume it is processed in China.

Self-host if you need control. If you like the model but not the data path, download the MIT-licensed weights and run them yourself.

Frequently asked questions

Is the DeepSeek app free?

Yes. DeepSeek is fully free with no paid consumer tier. You get DeepSeek V4, the DeepThink reasoning mode, web search, file uploads and a 1M-token context at no cost. Developers who want the same models programmatically pay per token through the API, which is separate from the app.

Is DeepSeek safe to use?

It is safe for everyday, non-sensitive tasks, but the hosted app stores data on servers in China, so it is not appropriate for confidential, personal or regulated information. Italy, Australia, South Korea and others have restricted it, and Germany has asked Apple and Google to delist it. For sensitive work, self-host the open-weight model or use an EU-based app like Le Chat.

What model does the DeepSeek app use?

The app runs DeepSeek V4 by default, released as a preview on 24 April 2026, with a 1M-token context window. Switching on DeepThink uses DeepSeek’s reasoning line (R1, then R2). DeepSeek V3.2 powered the app before V4.

What is DeepThink in DeepSeek?

DeepThink is DeepSeek’s reasoning mode. Toggling it on switches to the R-series model, which works through a problem step by step and shows its reasoning before answering. It is stronger on maths, logic and multi-step code but slower, with responses often taking 15–60 seconds.

Can DeepSeek generate images?

No. DeepSeek can analyse images you upload, but it cannot create them. There is no image or video generation in the app — for that, use ChatGPT, Gemini or Qwen.

Where is my DeepSeek data stored?

On servers in the People’s Republic of China, according to DeepSeek’s privacy policy. Under China’s 2017 National Intelligence Law, companies can be required to assist state intelligence work. To avoid the China data path while keeping the same model, self-host the MIT-licensed weights or run them through a non-Chinese cloud.

Is DeepSeek better than ChatGPT?

For free reasoning on a budget, DeepSeek is exceptional value and competitive on maths and code. ChatGPT is the stronger all-round app — image and video generation, real-time voice, memory and US data handling — and has paid tiers for heavier use. The right choice depends on whether price or breadth and data residency matter more.

Why is DeepSeek so cheap?

DeepSeek trained efficient Mixture-of-Experts models and open-sourced the weights under the MIT licence, and it monetises through a low-cost API rather than the consumer app. The app is a free shop window for models that are genuinely inexpensive to run, which is how it can offer frontier-class reasoning at no charge.

Verdict

DeepSeek is the best free reasoning app available, full stop — DeepSeek V4 and the DeepThink mode deliver frontier-adjacent maths, logic and coding with no paid tier, a 1M-token context and open weights you can self-host. The catch is not capability but trust: the hosted app stores data in China and is banned or restricted across a growing list of governments.

Use it for free, everyday, non-sensitive work — study, drafting, explanations, code you are happy to share. Avoid it for anything confidential or regulated, where the China data path is disqualifying. The neat resolution for technical users is to like the model and skip the app: the same MIT-licensed weights run on your own hardware with none of the residency concerns. As a free consumer chat, DeepSeek is outstanding; as a home for sensitive data, it is the wrong choice, and that single distinction should drive the decision.

Official links