Question 1

What is DeepSeek V3.1 Terminus?

Accepted Answer

DeepSeek V3.1 Terminus is a model from Deepseek, released on Sep 22, 2025. DeepSeek-V3.1 Terminus is an update to DeepSeek V3.1 that maintains the model's original capabilities while addressing issues reported by users, including language consistency and agent capabilities, further optimizing the model's performance in coding and search agents. $0.27 per million input tokens, $0.95 per million output tokens. 163,840 token context window, maximum output of 32,768 tokens. Higher uptime with 5 providers. Includes independent benchmarks from Artificial Analysis.

Question 2

How much does DeepSeek V3.1 Terminus cost?

Accepted Answer

On the Respan gateway, input starts at $0.27 per 1M tokens on OpenRouter, and output starts at $1.00 per 1M tokens on OpenRouter, after gateway discounts.

Question 3

Which providers serve DeepSeek V3.1 Terminus on Respan?

Accepted Answer

DeepSeek V3.1 Terminus is served by OpenRouter.

Question 4

What is DeepSeek V3.1 Terminus's context window?

Accepted Answer

DeepSeek V3.1 Terminus accepts up to 164K tokens of context.

Question 5

How do I use DeepSeek V3.1 Terminus with the Respan gateway?

Accepted Answer

Point any OpenAI-compatible SDK at https://api.respan.ai/api/ with your Respan API key and set the model to "deepseek-v3.1-terminus". To set it up with a coding agent, copy the agent setup prompt at the top of this page.

Question 6

How fast is DeepSeek V3.1 Terminus?

Accepted Answer

Over the last 30 days of requests through the Respan gateway, the fastest provider was OpenRouter at 15 tokens per second, and the lowest response latency was 3.3 seconds on OpenRouter. Speed varies with request size and provider.

Question 7

Where does DeepSeek V3.1 Terminus rank on the Respan Index?

Accepted Answer

DeepSeek V3.1 Terminus scores 18.7 out of 100 on the Respan Index v1.1, ranking #99 of 138 models. By category: Coding 5.4, Agents 16.8, Reasoning 16.5, Knowledge & language 19.9, and Human preference 46.7. The Respan Index combines independent and lab-reported benchmark results into one score, using benchmark data collected by llmmetric.com.

Question 8

How does DeepSeek V3.1 Terminus score on benchmarks?

Accepted Answer

DeepSeek V3.1 Terminus has 12 published benchmark scores, including Aider-Polyglot 76.1%, SimpleQA (agentic tool use) 96.8%, and GPQA-Diamond 80.7%. Each score links to where it was published; the data is collected by llmmetric.com.

DeepSeek V3.1 Terminus

Providers

Pricing

Cost by volume

Throughput and latency

Output speed

Response latency

Certified where it counts.

Benchmarks

Respan Indexv1.1

Coding5

Agents3

Reasoning2

Knowledge1

Arena1

Apps