text model comparison
Claude Fable 5 vs Claude Opus 4.8
Claude Fable 5 and Claude Opus 4.8 are both current text models, from Anthropic. Claude Opus 4.8 is 50% cheaper per 1M input tokens than Claude Fable 5, $5 vs $10. On Arena Text, Claude Fable 5 scores 1504 Elo and Claude Opus 4.8 1481 Elo (Arena, measured October 8, 2026). Both accept 1,000,000 tokens of context.
Data verified October 12, 2026 · Dataset 2026-10-13
Side by side
Standard-tier prices in effect today. The better value in each row is highlighted.
| Fact | Claude Fable 5 | Claude Opus 4.8 |
|---|---|---|
| Price per 1M input tokens | $10 | $5 (better) |
| Price per 1M output tokens | $50 | $25 (better) |
| Cost of 10M input and 2M output tokens | $200 | $100 (better) |
| Arena Text | 1504 Elo (#3 of 49) (better) | 1481 Elo (#16 of 49) |
| GPQA Diamond | 85.9% (#33 of 40) | 91% (#21 of 40) (better) |
| FrontierMath Tiers 1-3 (v2) | 87% (#8 of 40) (better) | 80% (#13 of 40) |
| SimpleQA Verified | 70.7% (#6 of 36) (better) | 53% (#17 of 36) |
| LiveBench Overall | Not measured | 78.93 points (#2 of 5) |
| Provider | Anthropic | Anthropic |
| Release date | June 9, 2026 | May 28, 2026 |
| Access | API only | API only |
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens | Not reported |
| Input | text, image | text |
| Output | text | text |
Scores:Arena · 2026-10-12Epoch AI · 2026-10-12LiveBench · 2026-06-25
When to choose each
Claude Fable 5
Best for
- Long-horizon coding, reasoning, and knowledge-work evaluations
Watch out for
- Fable requires 30-day data retention, and classifier-triggered requests fall back to Claude Opus 4.8
Claude Opus 4.8
Best for
- Long-running agentic and professional-work evaluations
Watch out for
- Maximum output length is not represented because the approved source set does not establish one unambiguously
Claude Fable 5 vs Claude Opus 4.8 FAQ
Which is cheaper, Claude Fable 5 or Claude Opus 4.8?
Claude Opus 4.8 is 50% cheaper per 1M input tokens than Claude Fable 5, $5 vs $10. For 10M input and 2M output tokens, Claude Fable 5 costs $200 and Claude Opus 4.8 $100 at standard rates.
Which scores higher on independent benchmarks, Claude Fable 5 or Claude Opus 4.8?
Claude Fable 5 leads on Arena Text, 1504 Elo to 1481 Elo; Claude Opus 4.8 leads on GPQA Diamond, 91% to 85.9%; Claude Fable 5 leads on FrontierMath Tiers 1-3 (v2), 87% to 80%. Scores are independent evaluations, not either vendor's launch figures.
Which has the larger context window, Claude Fable 5 or Claude Opus 4.8?
Both accept 1,000,000 tokens of context.
Related comparisons
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- Claude Fable 5 vs GPT-6 Astra
- Claude Opus 4.8 vs Claude Opus 5
- Claude Opus 4.8 vs Claude Opus 5.5
- Claude Opus 4.8 vs Gemini 3.5 Flash
- Claude Opus 4.8 vs Gemini 3.8 Flash
Production evaluation
Choosing between Claude Fable 5 and Claude Opus 4.8?
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