Electricity Bench

claude-sonnet-5 vs gpt-5.6-sol

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-sonnet-5Clears tier 2 (partial tier 5) at 6.0% of Claude Max 20x per runDOVERALLgpt-5.6-solClears tier 4 (partial tier 5) at 3.5% of ChatGPT Plus per runCOVERALL
real-world@v3DvsC
Dimensionclaude-sonnet-5gpt-5.6-solAdvantage
Capability50%60%+10% (gpt-5.6-sol leads)
Median task time4m 22s2m 28s1m 53s faster (gpt-5.6-sol leads)
Approx. task cost$0.005 / task$0.011 / task$0.005 / task lower (claude-sonnet-5 leads)

claude-sonnet-5: 6.0% of Claude Max 20x (6.0% / 5h, 1.0% / 1w) per run. gpt-5.6-sol: 3.5% of ChatGPT Plus (3.5% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.

spec-planning@v1DvsC
Dimensionclaude-sonnet-5gpt-5.6-solAdvantage
Capability39%67%+28% (gpt-5.6-sol leads)
Median task time4m 38s4m 11s27s faster (gpt-5.6-sol leads)
Approx. task cost$0.010 / task$0.010 / task$0.000 / task lower (gpt-5.6-sol leads)

claude-sonnet-5: 3.0% of Claude Max 20x (3.0% / 5h) per run. gpt-5.6-sol: 0.9% of ChatGPT Plus (0.9% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.

vibe-coding@v1FvsC
Dimensionclaude-sonnet-5gpt-5.6-solAdvantage
Capability34%56%+22% (gpt-5.6-sol leads)
Median task time5m 17s3m 43s1m 33s faster (gpt-5.6-sol leads)
Approx. task cost$0.008 / task$0.011 / task$0.003 / task lower (claude-sonnet-5 leads)

claude-sonnet-5: 0.6% of Claude Max 20x (0.6% / 5h) per good solve. gpt-5.6-sol: 0.2% of ChatGPT Plus (0.2% / 1w) per good solve. Each figure is a share of that agent's own plan, so there is no delta to draw.

Grades and deltas are comparable only within a suite version. See methodology.

Frequently asked questions

Which is better for coding, claude-sonnet-5 or gpt-5.6-sol?

gpt-5.6-sol clears higher: tier 4 of 5 versus tier 2 for claude-sonnet-5 on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-08-18.

How much do claude-sonnet-5 and gpt-5.6-sol cost?

claude-sonnet-5 runs on Claude Max 20x at $200/month (public price as of 2026-08-05). gpt-5.6-sol runs on ChatGPT Plus at $20/month (public price as of 2026-07-20).