DeepSeek V3.1 Terminus (DeepSeek) and DeepSeek V4 Pro 0813 (DeepSeek) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.
Snapshot as of 9 September 2026
As of 9 September 2026, DeepSeek V4 Pro 0813 holds the stronger ModelCap Index position (#20 vs #62); DeepSeek V3.1 Terminus is 1.7× cheaper per output token ($1.00/1M vs $1.74/1M); and DeepSeek V4 Pro 0813 offers the longer context window (1M vs 164K tokens).
Evidence: 3 public benchmark observations across 3 boards · 4 public benchmark observations across 4 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.
Benchmark scores: DeepSeek V3.1 Terminus vs DeepSeek V4 Pro 0813
Public benchmark boards where DeepSeek V3.1 Terminus or DeepSeek V4 Pro 0813 has a published result
DeepSeek V3.1 Terminus vs DeepSeek V4 Pro 0813: common questions
Is DeepSeek V3.1 Terminus better than DeepSeek V4 Pro 0813?
DeepSeek V4 Pro 0813 ranks higher on the ModelCap Index as of 9 September 2026: #20 against #62. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it. Their published uncertainty intervals do not overlap, but the aggregate Index does not predict performance on every task; compare the relevant benchmark configurations before choosing.
Is DeepSeek V3.1 Terminus cheaper than DeepSeek V4 Pro 0813?
DeepSeek V3.1 Terminus is cheaper on output tokens: $1.00/1M against $1.74/1M. Input tokens are $0.27/1M for DeepSeek V3.1 Terminus and $0.579/1M for DeepSeek V4 Pro 0813. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens. For 1,000 requests with 2,000 input and 500 output tokens each (2M input + 0.5M output), the listed-rate estimate is $1.04 for DeepSeek V3.1 Terminus versus $2.03 for DeepSeek V4 Pro 0813. DeepSeek V3.1 Terminus costs 48.7% less in this scenario. This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the selected endpoint before budgeting.
Which has the bigger context window, DeepSeek V3.1 Terminus or DeepSeek V4 Pro 0813?
DeepSeek V4 Pro 0813 has the larger context window: 1M tokens against 164K.
Which is better for coding, DeepSeek V3.1 Terminus or DeepSeek V4 Pro 0813?
Arena coding: DeepSeek V3.1 Terminus 1461, DeepSeek V4 Pro 0813 1505 — DeepSeek V4 Pro 0813 leads. AA Terminal-Bench 2.1: DeepSeek V3.1 Terminus 44.9%, DeepSeek V4 Pro 0813 78.7% — DeepSeek V4 Pro 0813 leads.
Are DeepSeek V3.1 Terminus and DeepSeek V4 Pro 0813 open-weight models?
DeepSeek V3.1 Terminus: Open weights. DeepSeek V4 Pro 0813: Open weights. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.
Where can I run DeepSeek V3.1 Terminus and DeepSeek V4 Pro 0813?
ModelCap currently lists 4 API providers for DeepSeek V3.1 Terminus and 19 for DeepSeek V4 Pro 0813, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.
How current is this DeepSeek V3.1 Terminus vs DeepSeek V4 Pro 0813 comparison?
Every figure comes from the sealed ModelCap dataset published 9 September 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.