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HEAD TO HEAD · UPDATED NOV 6, 2026
Claude Fable 5.1 vs Grok 4.7
Anthropic against xAI, on sourced numbers only. Green marks the higher (or cheaper) value on each row; the text below only calls a lead when the gap is bigger than measurement noise.
| Claude Fable 5.1 | Grok 4.7 | |
|---|---|---|
| Arena Elo | 1504 source ↗ | 1441 source ↗ |
| GPQA Diamond | not published | not published |
| $ per 1M in / out | $10 / $50 source ↗ | $2 / $6 source ↗ |
| Blended $ per 1M (3:1) | $20.00 source ↗ | $3.00 source ↗ |
| Context window | 1M source ↗ | 500K source ↗ |
| Output speed | not published | 72 tok/s source ↗ |
| Released | Sep 1, 2026 source ↗ | Sep 21, 2026 source ↗ |
| Open weights | No source ↗ | No source ↗ |
| Reasoning effort tiers | low · medium · high · xhigh · max (default: high) | low · medium · high · xhigh (default: high) |
| API effort control | output_config={"effort": "low" | "medium" | "high" | "xhigh" | "max"} source ↗ | reasoning_effort="low" | "medium" | "high" | "xhigh" source ↗ |
| Additional benchmarks | Terminal-Bench 4.0: 55.8% source ↗ GDPval-AA v2.1: 1735 source ↗ AA Intelligence Index v5.0.1: 50 source ↗ | DeepSWE v1.1: 71.0% source ↗ CursorBench 4.0: 46.3% source ↗ AA Intelligence Index v5.0.1: 35 (xhigh) source ↗ |
| Best for (workload) | Anthropic's most capable generally available model, for demanding reasoning and long-horizon agentic work (Anthropic). source ↗ | xAI's flagship. Reasoning is always on and cannot be turned off; 500K context; 71.0% on DeepSWE v1.1 (xAI). source ↗ |
Arena Elo from the arena.ai text leaderboard as of Oct 27, 2026 source ↗. Speed measured by Artificial Analysis and varies by provider.
Which one should I use?
For high-volume work where cost matters most, Grok 4.7 is about 6.7 times cheaper per token. For overall answer quality as rated by people in blind tests, Claude Fable 5.1 leads clearly (1504 vs 1441 Arena Elo). On release timing, Anthropic is at day 30 of a typical ~15-day gap (PAST TYPICAL GAP), and xAI is at day 46 of a typical ~46-day gap (PAST TYPICAL GAP).
Key differences from the sourced numbers
- Grok 4.7 is the cheaper option: $3.00 vs $20.00 per 1M tokens at a 3:1 input-to-output mix (about 6.7 times less).
- Claude Fable 5.1 scores 63 Elo points higher (1504 vs 1441) on the Arena text leaderboard, where people vote on blind side-by-side answers.
- Claude Fable 5.1 pricing note: Same rate across the full 1M context window.
- Grok 4.7 pricing note: Prompts under 200K tokens; $4 / $12 above 200K.
Frequently asked questions
Is Claude Fable 5.1 or Grok 4.7 better?
Grok 4.7 is the cheaper option: $3.00 vs $20.00 per 1M tokens at a 3:1 input-to-output mix (about 6.7 times less). Claude Fable 5.1 scores 63 Elo points higher (1504 vs 1441) on the Arena text leaderboard, where people vote on blind side-by-side answers. Claude Fable 5.1 pricing note: Same rate across the full 1M context window. Grok 4.7 pricing note: Prompts under 200K tokens; $4 / $12 above 200K.
Which one should I use: Claude Fable 5.1 or Grok 4.7?
For high-volume work where cost matters most, Grok 4.7 is about 6.7 times cheaper per token. For overall answer quality as rated by people in blind tests, Claude Fable 5.1 leads clearly (1504 vs 1441 Arena Elo). On release timing, Anthropic is at day 30 of a typical ~15-day gap (PAST TYPICAL GAP), and xAI is at day 46 of a typical ~46-day gap (PAST TYPICAL GAP).
How much does Claude Fable 5.1 cost compared with Grok 4.7?
Claude Fable 5.1 lists at $10 / $50 per 1M input/output tokens ($20.00/1M blended at 3:1). Grok 4.7 lists at $2 / $6 per 1M input/output tokens ($3.00/1M blended at 3:1).
Facts checked Nov 5, 2026 against official sources. Every number links to its source. Spotted an error? Email [email protected].