Claude Fable 5.1 vs Grok 4.6
Grok 4.6 was superseded by Grok 4.7. The grades below are the last ones measured, so read them as history rather than as this week's board. See the current roster.
Claude Fable 5.1 leads overall, B- to C-. Claude Fable 5.1 is about 1.6x cheaper per task. By suite, Claude Fable 5.1 takes real-world issues (B+ to D) and spec planning (C+ to C). The data gives no reason to pick Grok 4.6 over Claude Fable 5.1 this week.Measured
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.
Verdict: Grok 4.6 vs Claude Fable 5.1
Claude Fable 5.1 leads overall, B- to C-. By suite: Claude Fable 5.1 takes real-world issues, B+ to D (87% vs 47% capability); Claude Fable 5.1 takes spec planning, C+ to C (71% vs 66% capability); Claude Fable 5.1 takes vibe coding, C+ to C- (74% vs 61% capability). Claude Fable 5.1 used 8% of Claude Max 5x's weekly limit per pass, $0.097 per task at the listed price. Grok 4.6 used 13% of SuperGrok Plus's weekly limit per pass, $0.157 per task at the listed price. Per task, Claude Fable 5.1 is about 1.6x cheaper ($0.097 vs $0.157). Claude Fable 5.1 is faster on real-world issues: a median task takes 3m 38s against 7m 10s. Both finished every task on it. The data gives no reason to pick Grok 4.6 over Claude Fable 5.1 this week.
Changed since the previous graded week: Claude Fable 5.1: real-world issues D+ to B+, real-world issues usage 7% to 5% of the weekly limit, spec planning usage 4% to 3% of the weekly limit, vibe coding C- to C+, vibe coding usage 0.6% to 0.4% of the weekly limit; Grok 4.6: real-world issues C- to D, real-world issues usage 4% to 3% of the weekly limit, vibe coding C+ to C-.
| Dimension | Claude Fable 5.1 | Grok 4.6 | Advantage |
|---|---|---|---|
| Capability | 87% | 47% | +40% (Claude Fable 5.1 leads) |
| Median task time | 3m 38s | 7m 10s | 3m 33s faster (Claude Fable 5.1 leads) |
| Approx. task cost | $0.077 / task | $0.046 / task | $0.031 / task lower (Grok 4.6 leads) |
Claude Fable 5.1: 64.0% of Claude Max 5x (64.0% / 5h, 5.0% / 1w) per run. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. Grok 4.6: 3.0% of SuperGrok Plus (3.0% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
| Dimension | Claude Fable 5.1 | Grok 4.6 | Advantage |
|---|---|---|---|
| Capability | 71% | 66% | +5% (Claude Fable 5.1 leads) |
| Median task time | 8m 55s | 45m 26s | 36m 31s faster (Claude Fable 5.1 leads) |
| Approx. task cost | $0.172 / task | $0.575 / task | $0.402 / task lower (Claude Fable 5.1 leads) |
Claude Fable 5.1: 33.0% of Claude Max 5x (33.0% / 5h, 3.0% / 1w) per run. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. Grok 4.6: 10.0% of SuperGrok Plus (10.0% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
| Dimension | Claude Fable 5.1 | Grok 4.6 | Advantage |
|---|---|---|---|
| Capability | 74% | 61% | +13% (Claude Fable 5.1 leads) |
| Median task time | 4m 14s | 11m 14s | 7m 0s faster (Claude Fable 5.1 leads) |
| Approx. task cost | $0.092 / task | <$0.230 / task | $0.138 / task lower (Claude Fable 5.1 leads) |
Claude Fable 5.1: 4.2% of Claude Max 5x (4.2% / 5h, 0.4% / 1w) per good solve. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. Grok 4.6: under 1% of SuperGrok Plus 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 Fable 5.1 or Grok 4.6?
Both clear tier 4 of 5, but Claude Fable 5.1 scores higher on capability: 87% versus 47% on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-09-27.
Which is cheaper per task, Claude Fable 5.1 or Grok 4.6?
Claude Fable 5.1 used 8% of Claude Max 5x's weekly limit per pass, $0.097 per task at the listed price. Grok 4.6 used 13% of SuperGrok Plus's weekly limit per pass, $0.157 per task at the listed price. Per task, Claude Fable 5.1 is about 1.6x cheaper ($0.097 vs $0.157).
What do Claude Fable 5.1 and Grok 4.6 cost a month?
Claude Fable 5.1 runs on Claude Max 5x at $100/month (public price as of 2026-07-27). Grok 4.6 runs on SuperGrok Plus at $100/month (public price as of 2026-09-14).