claude-sonnet-5 vs kimi-k3-256k
Each agent graded on the same private suites, running headless through its own tools. Advantages are oriented so a win is a win, whichever way the metric runs.
| Dimension | claude-sonnet-5 | kimi-k3-256k | Advantage |
|---|---|---|---|
| Capability | 50% | 57% | +7% (kimi-k3-256k leads) |
| Median task time | 4m 22s | 3m 3s | 1m 19s faster (kimi-k3-256k leads) |
| Approx. task cost | $0.005 / task | $0.018 / task | $0.012 / task lower (claude-sonnet-5 leads) |
claude-sonnet-5: 6.0% of Claude Max 20x (6.0% / 5h, 1.0% / 1w) per run. kimi-k3-256k: 99.0% of Kimi Allegretto (99.0% / 5h, 20.0% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
Work per window: claude-sonnet-5 2435 vs kimi-k3-256k 148 suite runs per month (claude-sonnet-5 leads); per plan-dollar: 12.18 vs 3.78 (claude-sonnet-5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.
| Dimension | claude-sonnet-5 | kimi-k3-256k | Advantage |
|---|---|---|---|
| Capability | 39% | 51% | +12% (kimi-k3-256k leads) |
| Median task time | 4m 38s | 5m 16s | 38s faster (claude-sonnet-5 leads) |
| Approx. task cost | $0.010 / task | $0.034 / task | $0.024 / task lower (claude-sonnet-5 leads) |
claude-sonnet-5: 3.0% of Claude Max 20x (3.0% / 5h) per run. kimi-k3-256k: 51.0% of Kimi Allegretto (51.0% / 5h, 10.0% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
Work per window: claude-sonnet-5 4870 vs kimi-k3-256k 286 suite runs per month (claude-sonnet-5 leads); per plan-dollar: 24.35 vs 7.35 (claude-sonnet-5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.
| Dimension | claude-sonnet-5 | kimi-k3-256k | Advantage |
|---|---|---|---|
| Capability | 34% | 38% | +4% (kimi-k3-256k leads) |
| Median task time | 5m 17s | 6m 37s | 1m 21s faster (claude-sonnet-5 leads) |
| Approx. task cost | $0.008 / task | $0.027 / task | $0.019 / task lower (claude-sonnet-5 leads) |
claude-sonnet-5: 0.6% of Claude Max 20x (0.6% / 5h) per good solve. kimi-k3-256k: 10.2% of Kimi Allegretto (10.2% / 5h, 2.0% / 1w) per good solve. Each figure is a share of that agent's own plan, so there is no delta to draw.
Work per window: claude-sonnet-5 24350 vs kimi-k3-256k 1432 good solves per month (claude-sonnet-5 leads); per plan-dollar: 121.75 vs 36.73 (claude-sonnet-5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.
Grades and deltas are comparable only within a suite version. See methodology.
Frequently asked questions
Which is better for coding, claude-sonnet-5 or kimi-k3-256k?
Both clear tier 2 of 5, but kimi-k3-256k scores higher on capability: 57% versus 50% on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-08-18.
Which gives more work per dollar, claude-sonnet-5 or kimi-k3-256k?
claude-sonnet-5 delivers more benchmark work per subscription dollar: 12.18 suite runs per plan-dollar versus 3.78 for kimi-k3-256k (at $200/month priced 2026-08-05, and $39/month priced 2026-07-20). Work figures compare outputs, so unlike raw quota shares they are comparable across plans.
How much do claude-sonnet-5 and kimi-k3-256k cost?
claude-sonnet-5 runs on Claude Max 20x at $200/month (public price as of 2026-08-05). kimi-k3-256k runs on Kimi Allegretto at $39/month (public price as of 2026-07-20).