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Head-to-head comparison

Mercury 2 vs Qwen3.5-9B

Mercury 2 (Inception Labs) and Qwen3.5-9B (Qwen) 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 17 August 2026

As of 17 August 2026, Mercury 2 holds the stronger ModelCap Index position (#80 vs #83); Qwen3.5-9B is 5× cheaper per output token ($0.15/1M vs $0.75/1M); Qwen3.5-9B offers the longer context window (262K vs 128K tokens); and Qwen3.5-9B ships open weights.

Which should you choose?

Choose Mercury 2 if…

  • you want the stronger overall ModelCap Index position — #80 against #83 (31.2 vs 28.6 points).
  • Artificial Analysis Intelligence Index is your yardstick — 21.9 against 21.8.

Choose Qwen3.5-9B if…

  • API cost matters — $0.15/1M output tokens against $0.75/1M, about 5× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.10/1M against $0.25/1M.
  • you need the longer context window — 262K tokens against 128K.
  • you want to self-host: Qwen3.5-9B ships open weights while Mercury 2 is api only.
  • you want provider choice — 5 listed API providers against 1.
  • you want the more recently listed model — Qwen3.5-9B was listed 10 March 2026, Mercury 2 4 March 2026.

Mercury 2 vs Qwen3.5-9B: specs, pricing and context

Specification comparison of Mercury 2 and Qwen3.5-9B
FieldMercury 2Inception LabsQwen3.5-9BQwen
ModelCap Index position#80#83
Index score31.228.6
EvidenceMeasuredMeasured
Input price / 1M tokens$0.25$0.10
Output price / 1M tokens$0.75$0.15
Context window128K tokens262K tokens
Max output tokens50K262K
API providers listed15
Weight accessAPI onlyOpen weights
Input modalitiesTextText, Image, Video
First listed4 March 202610 March 2026
PublisherInception LabsQwen

Evidence: 3 public benchmark observations across 3 boards · 1 public benchmark observation across 1 board. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: Mercury 2 vs Qwen3.5-9B

Public benchmark boards where Mercury 2 or Qwen3.5-9B has a published result
BoardMercury 2Qwen3.5-9BLeads
Arena codingArena (LMArena)13941373–1415—Only one result
Artificial Analysis Intelligence IndexArtificial Analysis21.9intelligence-index21.8intelligence-indexMercury 2

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.

Mercury 2 vs Qwen3.5-9B: common questions

Is Mercury 2 better than Qwen3.5-9B?

Mercury 2 ranks higher on the ModelCap Index as of 17 August 2026: #80 against #83. 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.

Is Mercury 2 cheaper than Qwen3.5-9B?

Qwen3.5-9B is cheaper on output tokens: $0.15/1M against $0.75/1M. Input tokens are $0.25/1M for Mercury 2 and $0.10/1M for Qwen3.5-9B. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens.

Which has the bigger context window, Mercury 2 or Qwen3.5-9B?

Qwen3.5-9B has the larger context window: 262K tokens against 128K.

Which is better for coding, Mercury 2 or Qwen3.5-9B?

The two models do not share a coding benchmark board on ModelCap yet, so no head-to-head coding score is published; the ModelCap Index position is the closest overall signal.

Are Mercury 2 and Qwen3.5-9B open-weight models?

Mercury 2: API only. Qwen3.5-9B: 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 Mercury 2 and Qwen3.5-9B?

ModelCap currently lists 1 API provider for Mercury 2 and 5 for Qwen3.5-9B, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Mercury 2 vs Qwen3.5-9B comparison?

Every figure comes from the sealed ModelCap dataset published 17 August 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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