Head-to-head comparison
Nanbeige4.1 3B (Nanbeige) and Solar Pro 4 (Upstage) 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, Nanbeige4.1 3B holds the stronger ModelCap Index position (#90 vs #93); and Nanbeige4.1 3B ships open weights.
Evidence: global-corpus-prior over 182 held-out anchors (20%); launch card against 2 resolved peers on 6 rows (80%); exceeds every named peer on 5 of 6 rows; optimism haircut 3 from cross-lab-probe; shrunk 2.4 up toward the measured corpus · 3 public benchmark observations across 3 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.
Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.
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Nanbeige4.1 3B ranks higher on the ModelCap Index as of 9 September 2026: #90 against #93. 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 overlap, so the rank difference alone does not establish a reliable capability advantage for your workload.
At least one of the two has no listed API price on ModelCap right now, so no price comparison is made.
Both publish a —-token context window.
AA Terminal-Bench 2.1: Nanbeige4.1 3B 1.1%, Solar Pro 4 57.3% — Solar Pro 4 leads.
Nanbeige4.1 3B: Open weights. Solar Pro 4: API only. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.
ModelCap currently lists 0 API providers for Nanbeige4.1 3B and 1 for Solar Pro 4, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.
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.