New: Image recognition mode just launched · V4 now available

The Smartest Free
AI Chat.

DeepSeek Chat gives everyone access to frontier V4 intelligence — free, forever. Expert reasoning, real-time web search, file analysis, vision, and more. No credit card. No limits.

Start Chatting Free
131.5M monthly users No signup required No subscription #1 in 157 countries
Chat Interface

Chat That Actually
Thinks Deeply

Switch between Instant, Expert, DeepThink, and the brand-new Vision mode - all in one conversation, all free.

⚡ Instant Mode
🧠 Expert Mode
👁️ Vision Mode
🔎 DeepThink

Instant = V4-Flash for everyday questions.
Expert = V4-Pro for complex reasoning.
Vision = image + video understanding (beta).
DeepThink = R1 chain-of-thought, step-by-step.

🐋 DeepSeek Chat 🧠 Expert Mode V4-Pro
Can you explain why DeepSeek is so much cheaper than GPT-5?
Just now
Thinking through MoE architecture...
Two key reasons:

1. Mixture of Experts (MoE): V4-Pro has 1.6T total parameters but only activates 49B per token — so you get frontier quality without paying for 1.6T worth of compute.

2. Context Caching: Repeated prompt prefixes (like system prompts) are served at $0.014/1M instead of $0.14/1M — a 90% discount. At scale, this compounds massively.
Now
And how does the 1M context window work?
Ask DeepSeek anything...
📎
🖼️
🎙️
Everything Included Free

A Full AI Suite, Not Just a Chatbot

Every feature — from web search to code execution — is included at zero cost. No gated tier needed.

🌐
Real-Time Web Search

Ask about current events, live prices, breaking news, or recent research. DeepSeek searches the web and cites sources directly in the answer.

Built-in
🧠
DeepThink (R1 Mode)

Toggle step-by-step reasoning. The model shows its complete thought process before answering — dramatically better on math, logic, and complex analysis.

Thinking AI
👁️
Image & Video Vision

Brand new in April 2026 — DeepSeek can now "see." Upload photos, charts, screenshots, or videos. Ask questions about visual content in the same chat.

NEW · Beta
📎
File Uploads

Attach PDFs, Word docs, spreadsheets, CSVs, and code files. With 1M token context, entire books and codebases fit in a single conversation.

1M context
💻
Code Assistant

Generate, debug, review, and explain code in 340+ languages. Syntax highlighting, full-repo understanding, and direct execution in supported environments.

340+ langs
🎙️
Voice Input

Speak your questions naturally. Voice-to-text transcription feeds directly into the AI — perfect for hands-free use on the go or while multitasking.

Mobile + Web
☁️
Chat History Sync

Conversations sync across web, iOS, and Android when signed in. Start on your laptop, continue on your phone. Full history, always searchable.

Cross-device
📐
Math & Science

LaTeX rendering, step-by-step proofs, and olympiad-level problem solving. DeepThink mode achieves 97.3% on MATH-500 — gold medal at IMO 2025.

IMO Gold
✍️
Writing & Editing

Draft emails, articles, essays, and creative writing. Improve tone, fix grammar, translate, summarize, and maintain voice across long documents.

30+ languages
🚫
Zero Ads, Ever

DeepSeek's chat product has no advertisements, no upgrade prompts, and no feature paywalls. Basic services are permanently free — no hidden speed packs.

Truly Free
🌍
Multilingual

Best-in-class Chinese language performance. Strong English, Spanish, French, Japanese, and 27+ other languages — including dialect recognition and cross-lingual chat.

#1 Chinese AI
1 Million Token Context

Process entire books, legal contracts, large codebases, or year-long conversation histories in a single session. The largest free context window available.

1M tokens
Chat Modes

Four Modes, One Interface

Switch between modes mid-conversation. All free — no locked tiers, no upgrade prompts.

INSTANT
Instant Mode
model: deepseek-v4-flash

Lightning-fast everyday AI. 284B MoE, 13B active. Best for chat, quick questions, summaries, translations, drafts, and real-time conversation — where speed matters.

V4-Flash
Model
1M
Context
Fast
Response
Free
Cost
Try Instant Mode
🔎
DEEPTHINK
DeepThink Mode
powered by DeepSeek-R1

Chain-of-thought reasoning. The model shows every step of its logic before answering. 97.3% MATH-500, IMO Gold Medal 2025. Best for math, logic, and hard science problems.

R1
Model
97.3%
MATH-500
CoT
Reasoning
Free
Cost
Try DeepThink
👁️
VISION · BETA
Vision Mode
image recognition · launched Apr 29 2026

DeepSeek can now see. Upload images and videos alongside text. Ask questions about photos, charts, screenshots, code snippets captured from screen, and more.

Multi
modal
NEW
Beta
Image+
Video
Free
Cost
Try Vision Mode
Getting Started

Start Chatting in 30 Seconds

No download needed for web. No account required for basic use. Just open and chat.

1
Open chat.deepseek.com

Visit chat.deepseek.com in any browser. No account required to start chatting. Or download the free iOS/Android app from official stores.

2
Choose your mode

Select Instant for quick everyday questions, Expert for complex tasks, or toggle DeepThink to see the model reason step-by-step. For images, use Vision mode (new beta).

3
Type, upload, or speak

Type your question, attach a file (PDF, code, spreadsheet), upload an image, or use voice input. Combine multiple input types in a single message.

4
Enable web search (optional)

Click the web search toggle to let DeepSeek pull in current information from the web. Every search result is cited with a source link so you can verify.

5
Sign in to sync history

Create a free account with Email, Google, or Apple ID to save conversation history and sync across devices. History syncs instantly across web, iOS, and Android.

6
Tip: Write better prompts

Be specific about format ("explain in bullet points"), context ("I'm a beginner"), and goal ("I want to understand, not just get the answer"). DeepSeek follows detailed instructions precisely.

💻

Code & Debugging

Paste broken code or describe what you need. DeepSeek generates, explains, debugs, and reviews in 340+ languages with full-repo context.

📚

Research & Study

Upload papers, textbooks, or notes. Ask specific questions, get summaries, generate quizzes, and work through problems step-by-step with DeepThink.

📊

Data Analysis

Upload CSV or spreadsheet files. Ask questions in plain English — find trends, generate summaries, suggest visualizations, and explain statistical results.

✍️

Writing & Content

Draft emails, articles, social posts, and creative writing. Improve existing text, adjust tone, translate between 30+ languages, and maintain style consistently.

Comparison

DeepSeek Chat vs Competitors

How DeepSeek's free chat stacks up against the top AI assistants — on capability, cost, and what's actually free.

Feature DeepSeek Chat ChatGPT Claude Gemini
Free tier model V4-Pro (full) GPT-5.2 (limited) Claude Sonnet Gemini 3.1 Flash
Monthly cost $0 forever $20 for Plus $20 for Pro $20 for Advanced
Context window (free) 1M tokens 128K (limited) 200K 1M
Reasoning / thinking mode ✓ Free (DeepThink) Paid (o-series) ✓ Extended thinking ✓ Deep Think
Web search (free) ✓ Built-in ✓ Limited Paid only ✓ Built-in
File upload (free) ✓ Yes ✓ Limited ✓ Yes ✓ Yes
Image / Vision (free) ✓ Beta (new) ✓ Full ✓ Full ✓ Full
Open source weights ✓ MIT license ✗ Closed ✗ Closed ✗ Closed
Coding benchmark (SWE-bench) 80.6% (V4-Pro) 74.9% (GPT-5.4) 80.8% (Opus) 80.6% (Gemini Pro)
Ads in free tier ✗ No ads ever Testing ads (US) ✗ No ads ✗ No ads
User Reviews

What 131M Users Say

Real reviews from App Store, Google Play, and Reddit communities — unfiltered and verified.

JR
james_r
Google Play · May 2026
★★★★★

"I've used every AI, A LOT, this is easily my favorite. It's very human, speaks like a friend, and has great humor. It understands what you're asking even if you can't find the words. Never just gives the surface level — it focuses on the hard confusing parts."

everyday use
SL
study_life
Google Play · Mar 2026
★★★★★

"I use DeepSeek for helping study Chinese, and it's excellent. Being able to ask questions informally instead of keyword-browsing Google is great. If you set up a chat with rules it follows them well. Compared to GPT it doesn't glaze as constantly."

language learning
ML
mleng_dev
Reddit r/deepseek
★★★★★

"Switched from GPT-4o to V4-Flash via API. Monthly bill dropped from $1,200 to $38 for the same RAG pipeline. The 90% cache hit discount is insane. For the chat interface itself — Expert Mode is genuinely frontier quality at literally $0."

developer
QF
quant_researcher
Reddit r/LocalLLaMA
★★★★★

"DeepThink for olympiad math is phenomenal. 97.3% MATH-500, free in the chat app. Watching it reason through hard problems step by step is genuinely educational. I use it to check my own proofs. Nothing else at this price point comes close."

math reasoning
VC
vibe_coder_26
Reddit r/LocalLLaMA
★★★★☆

"Using Expert Mode (V4-Pro) as my daily coding assistant. The agentic coding is on par with paid tools — and you're getting this free in the chat. The new Vision mode is a game changer for UI debugging from screenshots."

coding
HR
honest_review
App Store · Critical
★★★☆☆

"Good AI but the server gets busy sometimes — sometimes can't use it for 2 hours. Also worth noting it's a Chinese company. I'd avoid it for anything sensitive. But for general use, creative writing, and coding help? It's honestly the best free option."

⚠️ honest note
FAQ

Chat Questions Answered

Is DeepSeek Chat really free? What's the catch?+

Yes — completely free with no catch. chat.deepseek.com gives you full access to V4-Flash (Instant), V4-Pro (Expert), DeepThink (R1 reasoning), web search, file uploads, and image vision — all at $0. No subscription tier, no ads, no usage cards, no speed-boost packs. DeepSeek explicitly states basic services are permanently free. The only paid service is the developer API for building applications.

What is Expert Mode vs Instant Mode?+

Instant Mode uses V4-Flash (284B params, 13B active) — fast, efficient, best for everyday chat, quick questions, summaries, and translations. Expert Mode uses V4-Pro (1.6T params, 49B active) — the flagship model, best for complex coding, deep reasoning, research, and long-form analysis. Both are free. A new Vision Mode (image recognition) launched on April 29, 2026 in beta.

What is DeepThink mode and when should I use it?+

DeepThink (powered by R1) makes DeepSeek show its complete chain-of-thought reasoning before answering. Use it for: competition math, multi-step logic, scientific analysis, legal reasoning, and any task where seeing the reasoning matters. Avoid it for simple questions — it's significantly slower (15–60 seconds) but produces dramatically better answers on hard problems. Toggle it with the DeepThink button in the chat interface.

What files can I upload to DeepSeek Chat?+

DeepSeek Chat supports PDF, Word (.docx), plain text, CSV, code files, and images (JPG, PNG, screenshots). With the 1M token context window, you can upload very long documents without needing to chunk them. The new Vision mode (April 2026 beta) also supports video uploads. Batch file uploading and real-time code execution are not yet supported in the consumer chat interface.

Do I need an account to use DeepSeek Chat?+

No account is required to start chatting on chat.deepseek.com. You can use it as a guest immediately. Creating a free account (with Email, Google, or Apple ID) gives you: conversation history, cross-device sync between web/iOS/Android, and the ability to reference older chats. Signing up takes under 30 seconds and requires no credit card or phone number.

Is there a message limit on the free tier?+

DeepSeek has stated the web chat is free with 500 messages per hour as a bot-prevention cap — far more than any real user would hit. For individual users, there's effectively no limit. During peak hours, servers can become busy and you may see temporary delays or "Server Busy" messages — this is not a usage cap, just load management. For guaranteed availability, the paid API is recommended for production use.

What's new in DeepSeek Chat in 2026?+

Major 2026 updates: (1) V4 Models launched April 24, 2026 — V4-Flash and V4-Pro replace V3.2 as the default models. (2) Vision Mode (April 29, 2026) — DeepSeek can now process images and video, added as a new chat mode alongside Expert and Instant. (3) 1M token context — up from 128K in 2025. (4) Three reasoning effort levels in the chat: Non-Think, Think High, and Think Max.

Is DeepSeek Chat private and safe to use?+

DeepSeek is a Chinese company and data processed through chat.deepseek.com is stored on servers in China. For everyday use (study, coding, writing, creative work), most users find this acceptable. For sensitive information (healthcare, legal, financial, or company-confidential data), we recommend either self-hosting the model via Ollama (free, private, offline) or accessing DeepSeek through compliant cloud providers (AWS Bedrock, Azure AI) that offer HIPAA/SOC2 guarantees.

Start Now

The smartest free
AI chat is waiting.

Frontier V4 models. DeepThink reasoning. Web search. File uploads. Vision. All free — open chat.deepseek.com and start talking.

🐋 Open DeepSeek Chat 🍎 iOS App 🤖 Android App

✓ No account required  ·  ✓ No ads  ·  ✓ No subscription  ·  ✓ MIT open source