UltraGPT
DeepSeek: 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...
Intelligence overview
163.8K tok
Context window
32.8K tok
Max output
What DeepSeek: DeepSeek V3.1 can do.
Reasoning
Extended reasoning
Works through problems step by step before answering, trading latency for accuracy on harder tasks.
Development
Tool calling
Calls external functions mid-response, then continues reasoning from the result.
Structured output
Returns responses constrained to a JSON schema, ready to parse without cleanup.
Streaming
Streams tokens as they're generated instead of waiting on the full response.
Performance
Design Arena — ranked #84 across 7 categories
Pay for what you use.
Every model in UltraGPT runs behind one flat subscription — this is the underlying per-token cost the catalog tracks.
$0.25 / 1M tok
$0.95 / 1M tok
Built for serious work.
Build
Generate and refactor code, with the ability to run and verify tool calls and return structured, parseable output.
Think
Works through multi-step problems with extended reasoning before it answers.
Research
Holds up to 163.8K tokens of source material in context without losing the thread.
Automate
Chains tool calls across multi-step workflows, reasoning between each one.
Ask DeepSeek: DeepSeek V3.1 anything.
A preview of the real UltraGPT composer — the model you see here is the model you get.
Continues in the UltraGPT app — one login, every model.
How DeepSeek: DeepSeek V3.1 stacks up.
The closest models in the catalog by provider, capability and score — real entries, pulled from the same directory.
Technical details.
Specification
- Context window
- 163.8K tokens
- Max output
- 32.8K tokens
- Input modalities
- Text
- Output modalities
- Text
- Knowledge cutoff
- Mar 31, 2025
- Release date
- Aug 21, 2025
- Streaming
- Supported
- Tool calling
- Supported
- JSON mode
- Supported
More from DeepSeek, and everything else.
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