DeepSeek V3.1
DeepSeek-V3.1 is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes via prompt templates. It extends the DeepSeek-V3 base with a two-phase long-context training process, reaching up to 128K tokens, and uses FP8 microscaling for efficient inference. Users can control the reasoning behaviour with the `reasoning` `enabled` boolean. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#enable-reasoning-with-default
Context window
This model accepts 164K tokens in one request (~123K words of text).
What fits in one request
- FitsShort documentAbout 1,500 words of text
- FitsLong documentAbout 37K words of text
- Won't fitSmall codebaseAbout 150K words of text
- Won't fitFull novelAbout 375K words of text
Specifications
Context size, pricing, and release info in one place.
- Context window
- 163,840 tokens (164K)
- Max output tokens
- 163,840 tokens (164K)
- Speed tier
- balanced
- Provider
- Deepseek
- Release date
- Aug 2025
- Input cost
- $0.200/M / 1M tokens
- Output cost
- $0.800/M / 1M tokens
Capabilities
See which features this model supports, such as vision, tools, and streaming.
- Tool use
- Can call external tools and APIs
- Supported
- Function calling
- Structured function call interface
- Supported
- Extended thinking
- Shows its chain-of-thought reasoning
- Supported
- Streaming
- Returns tokens as they are generated
- Supported
- Vision
- Accepts image inputs alongside text
- Not supported
- Web search
- Can browse the web during a request
- Not supported
- Batch API
- Process many requests asynchronously
- Not supported
- Prompt caching
- Reuse repeated prompt prefixes cheaply
- Not supported
Best for
Jump to a guide or ranking that matches each workload.
Compare DeepSeek V3.1
Open a side-by-side comparison with one click.
- DeepSeek V3.1 vs Amazon Titan Text Express
DeepSeek V3.1 has 290% larger context window
- DeepSeek V3.1 vs Amazon Titan Text Lite
DeepSeek V3.1 has 290% larger context window
- DeepSeek V3.1 vs Amazon Titan Text Premier
DeepSeek V3.1 has 290% larger context window
- DeepSeek V3.1 vs Claude Instant
DeepSeek V3.1 has 63% larger context window
- DeepSeek V3.1 vs Anthropic Claude
DeepSeek V3.1 has 63% larger context window
- DeepSeek V3.1 vs Codellama 34b Instruct
DeepSeek V3.1 has 3900% larger context window
Frequently asked questions
Short answers about context size and how this model behaves.
More from Deepseek
Other models by Deepseek in our catalog.
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