Claude Fable 5 vs Grok 4.5
Claude Fable 5 was superseded by Claude Fable 5.1. Grok 4.5 was superseded by Grok 4.7.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 leads overall, C to C-. Grok 4.5 is about 5.4x cheaper per task. By suite, real-world issues is even at C- and Claude Fable 5 takes vibe coding (C+ to C-). Take Grok 4.5 anyway when you want the side that is cheaper per task.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 4.5 vs Claude Fable 5
Claude Fable 5 leads overall, C to C-. By suite: real-world issues is even at C- (60% vs 60% capability); Claude Fable 5 takes vibe coding, C+ to C- (74% vs 59% capability). Only Claude Fable 5 has run spec planning. Claude Fable 5 used 7% of Claude Max 20x's weekly limit per pass, $0.169 per task at the listed price; at the ~$100 tier the board defaults to that is an estimated ~14% of Claude Max 5x's weekly limit (est, about $0.169 per task). Grok 4.5 used 6.9% of SuperGrok's weekly limit per pass, $0.032 per task at the listed price. Per task, Grok 4.5 is about 5.4x cheaper ($0.032 vs $0.169). Claude Fable 5 is faster on real-world issues: a median task takes 2m 37s against 3m 9s. Both finished every task on it. Reasons to pick Grok 4.5 anyway: it is cheaper per task ($0.032 vs $0.169).
Changed since the previous graded week: Claude Fable 5: real-world issues C+ to C-, vibe coding C to C+; Grok 4.5: real-world issues usage 8.0% to 6.9% of the weekly limit.
| Dimension | Claude Fable 5 | Grok 4.5 | Advantage |
|---|---|---|---|
| Capability | 60% | 60% | Even |
| Median task time | 2m 37s | 3m 9s | 33s faster (Claude Fable 5 leads) |
| Approx. task cost | $0.153 / task | $0.032 / task | $0.122 / task lower (Grok 4.5 leads) |
Claude Fable 5: 33.0% of Claude Max 20x (33.0% / 5h, 5.0% / 1w) per run. Its weekly limit holds about 7 of the week's 33.6 5h windows. Grok 4.5: 6.9% of SuperGrok (6.9% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
Only Claude Fable 5 has run this suite, so there is no head-to-head yet.
| Dimension | Claude Fable 5 | Grok 4.5 | Advantage |
|---|---|---|---|
| Capability | 74% | 59% | +15% (Claude Fable 5 leads) |
| Median task time | 5m 28s | 3m 40s | 1m 49s faster (Grok 4.5 leads) |
| Approx. task cost | $0.184 / task | $0.031 / task | $0.153 / task lower (Grok 4.5 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 of the week's 33.6 5h windows. Grok 4.5: 0.4% of SuperGrok (0.4% / 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 Fable 5 or Grok 4.5?
They are even on our ladder: both clear tier 4 of 5 at 60% capability on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-08-30.
Which is cheaper per task, Claude Fable 5 or Grok 4.5?
Claude Fable 5 used 7% of Claude Max 20x's weekly limit per pass, $0.169 per task at the listed price; at the ~$100 tier the board defaults to that is an estimated ~14% of Claude Max 5x's weekly limit (est, about $0.169 per task). Grok 4.5 used 6.9% of SuperGrok's weekly limit per pass, $0.032 per task at the listed price. Per task, Grok 4.5 is about 5.4x cheaper ($0.032 vs $0.169).
What do Claude Fable 5 and Grok 4.5 cost a month?
Claude Fable 5 runs on Claude Max 20x at $200/month (public price as of 2026-08-05). Grok 4.5 runs on SuperGrok at $30/month (public price as of 2026-07-20).