Electricity Bench

Claude Fable 5 vs Claude Fable 5.1

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 Fable 5Clears tier 4 (partial tier 5) at 33.0% of Claude Max 20x per runCOVERALLClaude Fable 5.1Clears tier 4 (partial tier 5) at 28.0% of Claude Max 20x per runBOVERALL
real-world@v3CvsC
DimensionClaude Fable 5Claude Fable 5.1Advantage
Capability60%73%+13% (Claude Fable 5.1 leads)
Median task time2m 37s1m 46s51s faster (Claude Fable 5.1 leads)
Approx. task cost$0.030 / task$0.026 / task$0.005 / task lower (Claude Fable 5.1 leads)

Claude Fable 5: 33.0% of Claude Max 20x (33.0% / 5h, 5.0% / 1w) per run. Its weekly limit holds about 7.2 of the week's 33.6 5h windows. Claude Fable 5.1: 28.0% of Claude Max 20x (28.0% / 5h, 5.0% / 1w) per run. Its weekly limit holds about 7.2 of the week's 33.6 5h windows. Each figure is a share of that agent's own plan, so there is no delta to draw.

Work per window: Claude Fable 5 443 vs Claude Fable 5.1 522 suite runs per month (Claude Fable 5.1 leads); per plan-dollar: 2.21 vs 2.61 (Claude Fable 5.1 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.

spec-planning@v1CvsC
DimensionClaude Fable 5Claude Fable 5.1Advantage
Capability63%74%+11% (Claude Fable 5.1 leads)
Median task time5m 32s6m 51s1m 19s faster (Claude Fable 5 leads)
Approx. task cost$0.034 / task$0.051 / task$0.017 / task lower (Claude Fable 5 leads)

Claude Fable 5: 10.0% of Claude Max 20x (10.0% / 5h, 2.0% / 1w) per run. Its weekly limit holds about 7.2 of the week's 33.6 5h windows. Claude Fable 5.1: 15.0% of Claude Max 20x (15.0% / 5h, 2.0% / 1w) per run. Its weekly limit holds about 7.2 of the week's 33.6 5h windows. Each figure is a share of that agent's own plan, so there is no delta to draw.

Work per window: Claude Fable 5 1461 vs Claude Fable 5.1 974 suite runs per month (Claude Fable 5 leads); per plan-dollar: 7.30 vs 4.87 (Claude Fable 5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.

vibe-coding@v1CvsB
DimensionClaude Fable 5Claude Fable 5.1Advantage
Capability74%85%+10% (Claude Fable 5.1 leads)
Median task time5m 28s3m 48s1m 41s faster (Claude Fable 5.1 leads)
Approx. task cost$0.038 / task$0.025 / task$0.014 / task lower (Claude Fable 5.1 leads)

Claude Fable 5: 2.8% of Claude Max 20x (2.8% / 5h, 0.4% / 1w) per good solve. Its weekly limit holds about 7.2 of the week's 33.6 5h windows. Claude Fable 5.1: 1.8% of Claude Max 20x (1.8% / 5h, 0.2% / 1w) per good solve. Its weekly limit holds about 7.2 of the week's 33.6 5h windows. Each figure is a share of that agent's own plan, so there is no delta to draw.

Work per window: Claude Fable 5 5218 vs Claude Fable 5.1 8117 good solves per month (Claude Fable 5.1 leads); per plan-dollar: 26.09 vs 40.58 (Claude Fable 5.1 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 Fable 5 or Claude Fable 5.1?

Both clear tier 4 of 5, but Claude Fable 5.1 scores higher on capability: 73% versus 60% on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-08-30.

Which gives more work per dollar, Claude Fable 5 or Claude Fable 5.1?

Claude Fable 5.1 delivers more benchmark work per subscription dollar: 2.61 suite runs per plan-dollar versus 2.21 for Claude Fable 5 (at $200/month priced 2026-08-05, and $200/month priced 2026-08-05). Work figures compare outputs, so unlike raw quota shares they are comparable across plans.

How much do Claude Fable 5 and Claude Fable 5.1 cost?

Claude Fable 5 runs on Claude Max 20x at $200/month (public price as of 2026-08-05). Claude Fable 5.1 runs on Claude Max 20x at $200/month (public price as of 2026-08-05).