Qwen 3.5 Plus (hosted 397B-A17B)
Qwen 3.5 Plus (hosted 397B-A17B) is an API-only (closed weights) language model from Qwen, released February 16, 2026. The context window is 1M tokens. On the Epoch Capabilities Index it scores 147.3, rank 82 of 256 rated models. API price: $0.4 input / $2.4 output per million tokens.
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Lab
Qwen
Released
February 16, 2026
Weights
API-only (closed weights)
Parameters
–
Context
1M
Price / M tokens
$0.4 / $2.4 in / out
Epoch ECI
147.3 #82
Strengths by category
ModelTape's 0–100 fit on Epoch AI benchmark results.
| Category | Score | Based on |
|---|---|---|
| Reasoning | 11.1 | Chess Puzzles, Mystery Game Puzzles |
| Math | 50.5 | OTIS Mock AIME 2024-2025, FrontierMath-2025-02-28-Private, FrontierMath-Tier-4-2025-07-01-Private |
| Knowledge | 65.5 | GPQA diamond, SimpleQA Verified |
Benchmark results
| Benchmark (Epoch AI) | Score |
|---|---|
| OTIS Mock AIME | 86.7% |
| GPQA Diamond | 83.1% |
| FrontierMath-2025-02-28-Private | 36.9% |
| SimpleQA Verified | 25.4% |
| Mystery Game Puzzles | 8.6% |
| Chess Puzzles | 4.3% |
| FrontierMath-Tier-4-2025-07-01-Private | 3.5% |
Links
Models with a similar score
GPT-5 Pro · Kimi K2.7 Code · GPT-5.1 · Beam 1.0 · Inkling-Small · GLM-5.1 · DeepSeek-V4-Pro · GPT-5
More from Qwen
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