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Head-to-head comparison

Qwen3.5-9B vs Solar Pro 4

Qwen3.5-9B (Qwen) 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 10 September 2026

As of 10 September 2026, Solar Pro 4 holds the stronger ModelCap Index position (#98 vs #100); Solar Pro 4 is 1.3× cheaper per output token ($0.12/1M vs $0.15/1M); Solar Pro 4 offers the longer context window (524K vs 262K tokens); and Qwen3.5-9B ships open weights.

Which should you choose?

Choose Qwen3.5-9B if…

  • you want to self-host: Qwen3.5-9B ships open weights while Solar Pro 4 is api only.
  • you want provider choice — 6 listed API providers against 1.

Choose Solar Pro 4 if…

  • you want the stronger overall ModelCap Index position — #98 against #100 (42.7 vs 41.5 points).
  • API cost matters — $0.12/1M output tokens against $0.15/1M, about 1.3× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.03/1M against $0.10/1M.
  • you need the longer context window — 524K tokens against 262K.
  • AA Terminal-Bench 2.1 is your yardstick — 57.3% against 29.2%.
  • AA Humanity's Last Exam is your yardstick — 29.2% against 14.9%.
  • you want the more recently listed model — Solar Pro 4 was listed 10 August 2026, Qwen3.5-9B 10 March 2026.

Qwen3.5-9B vs Solar Pro 4: specs, pricing and context

Specification comparison of Qwen3.5-9B and Solar Pro 4
FieldQwen3.5-9BQwenSolar Pro 4Upstage
ModelCap Index position#100#98
Index score41.542.7
EvidenceEstimatedMeasured
Input price / 1M tokens$0.10$0.03
Output price / 1M tokens$0.15$0.12
Context window262K tokens524K tokens
Max output tokens236K131K
API providers listed61
Weight accessOpen weightsAPI only
Input modalitiesText, Image, VideoText
First listed10 March 202610 August 2026
PublisherQwenUpstage

Evidence: publisher-corpus-prior over 184 held-out anchors (29%); launch card against 3 resolved peers on 10 rows (71%); exceeds every named peer on 4 of 10 rows; optimism haircut 0.6 from cross-lab-probe; shrunk 3.6 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.

Benchmark scores: Qwen3.5-9B vs Solar Pro 4

Public benchmark boards where Qwen3.5-9B or Solar Pro 4 has a published result
BoardQwen3.5-9BSolar Pro 4Leads
Arena codingArena (LMArena)—14471425–1470Only one result
LMArena AgentLMArena—-11.3%-15.0%–-7.5%Only one result
AA Terminal-Bench 2.1Artificial Analysis29.2%terminal-bench:2.1:terminus-2:e2b:pass-at-1:3-repeats:source-model="Qwen3.5 9B":reasoning=true57.3%terminal-bench:2.1:terminus-2:e2b:pass-at-1:3-repeats:source-model="Solar Pro 4":reasoning=trueSolar Pro 4
AA τ²-Bench TelecomArtificial Analysis86.8%tau2:telecom:dual-control:pass-at-1:3-repeats:source-model="Qwen3.5 9B":reasoning=true—Only one result
AA Humanity's Last ExamArtificial Analysis14.9%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="Qwen3.5 9B":reasoning=true29.2%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="Solar Pro 4":reasoning=trueSolar Pro 4

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

Qwen3.5-9B vs Solar Pro 4: common questions

Is Qwen3.5-9B better than Solar Pro 4?

Solar Pro 4 ranks higher on the ModelCap Index as of 10 September 2026: #98 against #100. 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.

Is Qwen3.5-9B cheaper than Solar Pro 4?

Solar Pro 4 is cheaper on output tokens: $0.12/1M against $0.15/1M. Input tokens are $0.10/1M for Qwen3.5-9B and $0.03/1M for Solar Pro 4. 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 $0.27 for Qwen3.5-9B versus $0.12 for Solar Pro 4. Solar Pro 4 costs 56.4% 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, Qwen3.5-9B or Solar Pro 4?

Solar Pro 4 has the larger context window: 524K tokens against 262K.

Which is better for coding, Qwen3.5-9B or Solar Pro 4?

AA Terminal-Bench 2.1: Qwen3.5-9B 29.2%, Solar Pro 4 57.3% — Solar Pro 4 leads.

Are Qwen3.5-9B and Solar Pro 4 open-weight models?

Qwen3.5-9B: 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.

Where can I run Qwen3.5-9B and Solar Pro 4?

ModelCap currently lists 6 API providers for Qwen3.5-9B and 1 for Solar Pro 4, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Qwen3.5-9B vs Solar Pro 4 comparison?

Every figure comes from the sealed ModelCap dataset published 10 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.

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