DeepSeek V4 is the latest model generation from DeepSeek. It launched in April 2026 with two models: V4 Pro, a large Mixture-of-Experts model with 1.6 trillion total and 49 billion active parameters for advanced reasoning and coding, and V4 Flash, a lighter and faster option.

Both support a context window of about 1 million tokens. In September 2026 DeepSeek released V4.1 Flash, the first model built on its new Causal Encoder-Decoder architecture, which can also take images as input.

Advanced Reasoning

Work through math, logic, and technical problems step by step.

Coding

Write, refactor, and debug code in many languages.

Agentic Task Execution

Plan multi-step work and call tools to complete it.

Long Document Context

Keep about 1M tokens in view - long reports or entire repositories.

Fast Flash Responses

Use V4 Flash for quick answers in everyday chat.

Open-Weight Models

DeepSeek publishes model weights so developers can run them themselves.

Open the chat

Click "Open Chat" to start chatting with DeepSeek for free.

Describe your task

Ask a question, paste code, or describe the result you need.

Get a reasoned answer

The model thinks through your request and answers step by step.

Refine the result

Ask follow-ups or request changes.

Use the output

Copy the answer or code into your project.

DeepSeek V4 is DeepSeek's latest model generation, launched in April 2026 with V4 Pro and V4 Flash.

V4 Pro is the large model for advanced reasoning and coding. V4 Flash is lighter and faster for everyday tasks.

About 1 million tokens.

DeepSeek releases its models with open weights, so developers can download and run them.

An update released in September 2026 and the first DeepSeek model on its Causal Encoder-Decoder architecture. It also accepts images.

Yes, the DeepSeek chat on chatai.org is free and requires no registration. There is a daily message limit.

DeepSeek V4: Open Models with 1M Context

What is DeepSeek V4?

What DeepSeek V4 can do

How to use DeepSeek V4

Frequently Asked Questions