Claude Opus 5.5 vs Hy4 preview: Specs & Benchmark Comparison
Claude Opus 5.5 is developed by Anthropic, while Hy4 preview comes from Tencent. Hy4 preview was released in August 2026, and Claude Opus 5.5 followed a month later in September 2026. Hy4 preview has a published size of about 770 billion parameters; Anthropic has not disclosed the parameter count of Claude Opus 5.5.
The two models share 9 published benchmarks. Claude Opus 5.5 leads on 9 of them. The widest gaps are on Program Bench, where Claude Opus 5.5 scores 91.2% against 17.5%; ArXivMath, where Claude Opus 5.5 scores 91.2% against 66.6%. Averaged across everything we track, Claude Opus 5.5 sits at 71.1% and Hy4 preview at 58.7%.
Claude Opus 5.5 is available through an API at $4 per million input tokens with a 1M-token context window. We do not track a hosted API for Hy4 preview, so pricing and context cannot be compared directly.
| Characteristic | Claude Opus 5.5 | Hy4 preview |
|---|---|---|
| Company | Anthropic | Tencent |
| Release Date | September 22, 2026 | August 28, 2026 |
| Parameters | — | 770B |
| Multimodal | Yes | No |
| Context (input) | 1.0M | — |
| Context (output) | 128K | — |
| Input Price / 1M | $4.00 | — |
| Output Price / 1M | $20.00 | — |
| Average Score | 71.1% | 58.7% |
| Benchmarks | ||
| Program Bench | 91.2% | 17.5% |
| ArXivMath | 91.2% | 66.6% |
| SWE-Bench Pro | 89.9% | 65.7% |
| Humanity's Last Exam (no tools, text-only) | 64.4% | 43.4% |
| BioMysteryBench | 89.3% | 71.3% |
| Humanity's Last Exam (with tools, text-only) | 67.7% | 55.4% |
| SWE-bench Multilingual | 93.9% | 82.9% |
| AutomationBench | 40.0% | 32.1% |
| OfficeQA Pro | 67.7% | 66.2% |
Visual Benchmark Comparison
Verdict
Claude Opus 5.5 leads in 1 out of 2 comparison categories.
Both models show comparable average scores: Claude Opus 5.5 — 0.7, Hy4 preview — 0.6.
Claude Opus 5.5 is newer: released 9/22/2026 vs 8/28/2026.
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Frequently Asked Questions
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The Claude Opus 5.5 and Hy4 preview comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the Claude Opus 5.5 or Hy4 preview page. See also the complete list of AI model comparisons.