Head-to-head comparison across 3benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Claude Fable 5
96
Grok 4.20
72
Verified leaderboard positions: Claude Fable 5 #2 · Grok 4.20 unranked
Pick Claude Fable 5 if you want the stronger benchmark profile. Grok 4.20 only becomes the better choice if you want the cheaper token bill or you need the larger 2M context window.
Agentic
+38.1 difference
Coding
+24.6 difference
Multimodal
+21.6 difference
Claude Fable 5
Grok 4.20
$10 / $50
$2 / $6
N/A
233 t/s
N/A
10.33s
1M+
2M
Pick Claude Fable 5 if you want the stronger benchmark profile. Grok 4.20 only becomes the better choice if you want the cheaper token bill or you need the larger 2M context window.
Claude Fable 5 is clearly ahead on the provisional aggregate, 96 to 72. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Fable 5's sharpest advantage is in agentic, where it averages 85.2 against 47.1. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 84.3% to 47.1%.
Claude Fable 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $2.00 input / $6.00 output per 1M tokens for Grok 4.20. That is roughly 8.3x on output cost alone. Grok 4.20 gives you the larger context window at 2M, compared with 1M+ for Claude Fable 5.
Claude Fable 5 is ahead on BenchLM's provisional leaderboard, 96 to 72. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 84.3% and 47.1%.
Claude Fable 5 has the edge for coding in this comparison, averaging 85.6 versus 61. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.
Claude Fable 5 has the edge for agentic tasks in this comparison, averaging 85.2 versus 47.1. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Claude Fable 5 has the edge for multimodal and grounded tasks in this comparison, averaging 92.4 versus 70.8. Inside this category, CharXiv is the benchmark that creates the most daylight between them.
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