text model comparison
Claude Fable 5.1 vs Grok 4.7
Claude Fable 5.1 and Grok 4.7 are both current text models, from Anthropic and xAI. Grok 4.7 is 80% cheaper per 1M input tokens than Claude Fable 5.1, $2 vs $10. On Arena Text, Claude Fable 5.1 scores 1501 Elo and Grok 4.7 1443 Elo (Arena, measured October 8, 2026). Claude Fable 5.1 has the larger context window, 1,000,000 vs 500,000 tokens.
Data verified October 12, 2026 · Dataset 2026-10-13
Side by side
Prices in effect today, compared at the same tier wherever both list one. The better value in each row is highlighted.
| Fact | Claude Fable 5.1 | Grok 4.7 |
|---|---|---|
| Price per 1M input tokens | $10 | $2 (better) |
| Price per 1M output tokens | $50 | $6 (better) |
| Arena Text | 1501 Elo (#4 of 49) (better) | 1443 Elo (#37 of 49) |
| FrontierMath Tiers 1-3 (v2) | 90.2% (#4 of 40) (better) | 53% (#32 of 40) |
| SimpleQA Verified | 70.8% (#5 of 36) (better) | 56% (#16 of 36) |
| GPQA Diamond | Not measured | 92.7% (#17 of 40) |
| Provider | Anthropic | xAI |
| Release date | September 1, 2026 | September 21, 2026 |
| Access | API only | API only |
| Context window | 1,000,000 tokens | 500,000 tokens |
| Max output | 128,000 tokens | Not reported |
| Input | text, image | text |
| Output | text | text |
What each costs
Example workloads at each provider's listed rates, then every other rate either one lists. The cheaper figure in each row is highlighted.
| Workload or rate | Claude Fable 5.1 | Grok 4.7 |
|---|---|---|
| 10M input and 2M output tokens | $200 | $32 (better) |
| The same, with 9M of the input tokens cached | $112.25 | $18.50 (better) |
| The same, through the batch API | $100 | Not listed |
| Other listed rates | ||
| 1M input tokens, cached | $0.25 (better) | $0.50 |
| 1M input tokens, 5-minute cache write | $12.50 | Not listed |
| 1M input tokens, 1-hour cache write | $20 | Not listed |
| 1M input tokens, batch | $5 | Not listed |
| 1M output tokens, batch | $25 | Not listed |
| 1M input tokens, prompts over 200K tokens | Not listed | $4 |
| 1M output tokens, prompts over 200K tokens | Not listed | $12 |
When to choose each
Claude Fable 5.1
Where it leads
- Higher Arena Text score, 1501 Elo vs 1443 Elo
- Higher FrontierMath Tiers 1-3 (v2) score, 90.2% vs 53%
- Higher SimpleQA Verified score, 70.8% vs 56%
- Larger context window 1,000,000 vs 500,000 tokens
- Accepts image input
- Cheaper cached input, $0.25 vs $0.50 per 1M tokens
- Batch pricing, $5 input and $25 output per 1M tokens
Best for
- Long-horizon agentic coding where a large prompt prefix is replayed across many turns
- Work where Claude Opus 5 at higher effort has already been evaluated and fell short
Watch out for
- Base input and output pricing is unchanged from Fable 5 at $10 / $50; the saving is entirely in cache reads, so a workload with little cache reuse sees no discount
- The 4.7-generation tokenizer produces roughly 30% more tokens for the same text than Claude Sonnet 4.6 and earlier, so per-token rates are not directly comparable across generations
- Anthropic’s launch comparisons are self-reported and were not reproduced independently here
Grok 4.7
Where it leads
- Lower input and output prices, $2 and $6 vs $10 and $50 per 1M tokens
Best for
- Output-heavy generation under the 200,000-token prompt line
- A cheaper alternative to the frontier tiers where 500k of context is enough
Watch out for
- The long-prompt threshold is 200,000 tokens, the lowest of any model here, and reaching it doubles input and output for the entire request
- xAI's model page does not state a maximum output for Grok 4.7, so it is recorded as unknown rather than inferred
- That page does not explicitly list image input for this model either, so it is catalogued as text-only
Claude Fable 5.1 vs Grok 4.7 FAQ
Which is cheaper, Claude Fable 5.1 or Grok 4.7?
Grok 4.7 is 80% cheaper per 1M input tokens than Claude Fable 5.1, $2 vs $10. For 10M input and 2M output tokens, Claude Fable 5.1 costs $200 and Grok 4.7 $32 at standard rates.
Which is cheaper with prompt caching, Claude Fable 5.1 or Grok 4.7?
Claude Fable 5.1 charges $0.25 per 1M cached input tokens, 98% below its standard input rate, and Grok 4.7 $0.50, 75% below. With 9M of 10M input tokens cached and 2M output tokens, Claude Fable 5.1 costs $112.25 and Grok 4.7 $18.50.
Which scores higher on independent benchmarks, Claude Fable 5.1 or Grok 4.7?
Claude Fable 5.1 leads on Arena Text, 1501 Elo to 1443 Elo; Claude Fable 5.1 leads on FrontierMath Tiers 1-3 (v2), 90.2% to 53%; Claude Fable 5.1 leads on SimpleQA Verified, 70.8% to 56%. Scores are independent evaluations, not either vendor's launch figures.
Which has the larger context window, Claude Fable 5.1 or Grok 4.7?
Claude Fable 5.1 has the larger context window, 1,000,000 vs 500,000 tokens.
How do Claude Fable 5.1 and Grok 4.7 differ in features?
Claude Fable 5.1 takes text and image input; Grok 4.7 takes text.
Articles on Claude Fable 5.1 and Grok 4.7
- Grok 4.7 vs Fable 5.1 vs GPT-6 Astra: Real Cost per TaskSeptember 23, 2026 · compares both
- Jev vs Fable 5.1 vs GPT-6 Astra: Which Model for Which JobSeptember 22, 2026
- GPT-6 Astra vs Fable 5.1: Two Scoreboards, Two WinnersSeptember 22, 2026
- Grok 4.7: Same Price as Grok 4.6, but Check Cost per TaskSeptember 22, 2026
- Claude Fable 5.1: Same Price, 75% Cheaper CacheSeptember 2, 2026
- Fable 5.1 vs Opus 5 vs GPT-5.6: Which to UseSeptember 1, 2026
Related comparisons
- Claude Fable 5.1 vs GPT-6 Astra
- Claude Sonnet 5.5 vs Grok 4.7
- Claude Fable 5.1 vs Claude Opus 4.8
- GPT-6 Luna vs Grok 4.7
- Claude Fable 5.1 vs Claude Opus 5
- Claude Sonnet 5 vs Grok 4.7
- Claude Fable 5.1 vs GPT-5.6 Sol
- GPT-6 Astra vs Grok 4.7
- Claude Fable 5 vs Claude Fable 5.1
- Grok 4.20 vs Grok 4.7
- Claude Fable 5.1 vs Gemini 4 Argon
- Grok 4.3 vs Grok 4.7
Production evaluation
Choosing between Claude Fable 5.1 and Grok 4.7?
Public benchmarks narrow the shortlist. We run both on your own tasks, data and cost limits, then build the routing and review controls to run the winner in production.
- A head-to-head evaluation on your real workload
- Routing between models by cost and difficulty