Electricity Bench

claude-opus-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.

claude-opus-5Clears tier 4 (partial tier 5) at 11.0% of Claude Max 20x per runCOVERALLkimi-k3-256kClears tier 2 (partial tier 5) at 99.0% of Kimi Allegretto per runDOVERALL
real-world@v3CvsC
Dimensionclaude-opus-5kimi-k3-256kAdvantage
Capability60%57%+3% (claude-opus-5 leads)
Median task time3m 57s3m 3s55s faster (kimi-k3-256k leads)
Approx. task cost$0.010 / task$0.018 / task$0.008 / task lower (claude-opus-5 leads)

claude-opus-5: 11.0% of Claude Max 20x (11.0% / 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-opus-5 1328 vs kimi-k3-256k 148 suite runs per month (claude-opus-5 leads); per plan-dollar: 6.64 vs 3.78 (claude-opus-5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.

spec-planning@v1CvsD
Dimensionclaude-opus-5kimi-k3-256kAdvantage
Capability63%51%+12% (claude-opus-5 leads)
Median task time5m 10s5m 16s6s faster (claude-opus-5 leads)
Approx. task cost$0.014 / task$0.034 / task$0.020 / task lower (claude-opus-5 leads)

claude-opus-5: 4.0% of Claude Max 20x (4.0% / 5h, 1.0% / 1w) 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-opus-5 3653 vs kimi-k3-256k 286 suite runs per month (claude-opus-5 leads); per plan-dollar: 18.26 vs 7.35 (claude-opus-5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.

vibe-coding@v1CvsD
Dimensionclaude-opus-5kimi-k3-256kAdvantage
Capability69%38%+31% (claude-opus-5 leads)
Median task time4m 59s6m 37s1m 38s faster (claude-opus-5 leads)
Approx. task cost$0.011 / task$0.027 / task$0.016 / task lower (claude-opus-5 leads)

claude-opus-5: 0.8% of Claude Max 20x (0.8% / 5h, 0.2% / 1w) 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-opus-5 18263 vs kimi-k3-256k 1432 good solves per month (claude-opus-5 leads); per plan-dollar: 91.31 vs 36.73 (claude-opus-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-opus-5 or kimi-k3-256k?

claude-opus-5 clears higher: tier 4 of 5 versus tier 2 for kimi-k3-256k on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-08-18.

Which gives more work per dollar, claude-opus-5 or kimi-k3-256k?

claude-opus-5 delivers more benchmark work per subscription dollar: 6.64 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-opus-5 and kimi-k3-256k cost?

claude-opus-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).