Claude Sonnet 5 vs Hy4 preview
| Spec | Claude Sonnet 5 | Hy4 preview |
|---|---|---|
| Respan Index | 46.7 (#39) | 47.7 (#38) |
| Blended price per 1M | $4 | $1.25 |
| Context window | 1M | 1M |
| Input / output per 1M | $2 / $10 | $0.834 / $2.5 |
| Max output | 128K | 64K |
| Input | text, vision | text |
| Released | 2026-06-30 | 2026-08-28 |
Respan Index by category
Each category is scored 0 to 100, and how far ahead the winner is. Leads under a point are close to even.
| Category | Claude Sonnet 5 | Hy4 preview |
|---|---|---|
| Coding | 26.9 Claude Sonnet 5 | 25.0 Hy4 preview |
| Agents | 62.8 Claude Sonnet 5 | 63.1 Hy4 preview |
| Reasoning | 51.0 Claude Sonnet 5 | 50.4 Hy4 preview |
| Knowledge & language | 34.0 Claude Sonnet 5 | 45.9* Hy4 preview |
| Human preference | 54.4 Claude Sonnet 5 | 56.8 Hy4 preview |
* Estimated: no published scores in that category. How the Respan Index works
Benchmarks both report
They split the 4 benchmarks both report evenly. Higher is better. Each score links to where it was published.
| Benchmark | Claude Sonnet 5 | Hy4 preview |
|---|---|---|
| LMArena Agent (LMArena) | 0.0294 | 0.0122 |
| LMArena WebDev (LMArena) | 1540 | 1631 |
| Terminal-Bench 4.0 (Vals AI) | 10.6% | 8.1% |
| GPQA Diamond | 90.5% | 92.3% |
FAQ
Is Claude Sonnet 5 better than Hy4 preview?
Hy4 preview scores 47.7 on the Respan Index (#38), ahead of Claude Sonnet 5 at 46.7 (#39). They split the 4 benchmarks both report evenly.
Which is cheaper, Claude Sonnet 5 or Hy4 preview?
Claude Sonnet 5 lists at $2 input and $10 output per 1M tokens; Hy4 preview at $0.834 and $2.5. Hy4 preview is 3.2x cheaper per token at list price.
Which has the larger context window?
Both accept 1M tokens of context.