Claude Fable 5 vs Claude Opus 4.8
Side-by-side comparison using current list prices and the live leaderboard.
Verdict
Claude Fable 5 is the stronger model; Claude Opus 4.8 is 2x cheaper.
- Claude Fable 5 ranks higher on the LMRank leaderboard (#1 vs #2).
- Claude Opus 4.8 is 2x cheaper per input token ($5.00 vs $10.00 per 1M).
- Both have a 1M-token context window.
At a Glance
| Attribute | Claude Fable 5 | Claude Opus 4.8 |
|---|---|---|
| Lab | Anthropic | Anthropic |
| Leaderboard rank | #1 | #2 |
| Tags | Long Context Coding Intelligent Reasoning Agentic | Intelligent Reasoning Multimodal Agentic |
| Context | 1M tokens | 1M tokens |
| Input price | $10.00/1M | $5.00/1M |
| Output price | $50.00/1M | $25.00/1M |
| Input modalities | Image and text | Text |
| Output modalities | Text | Text |
Claude Fable 5: strengths
- #1 Intelligence Index at 64.9
- 1M-token context window
- 95% on SWE-bench Verified
- Strong agentic and coding performance
- Vision and scientific research capable
Claude Opus 4.8: strengths
- Top-tier coding and reasoning benchmarks
- 1M token context window
- Strong agentic workflow support
- Wide cloud provider availability
Claude Fable 5: weaknesses
- Safety fallback reduces capability on sensitive queries
- Access may still be capacity-constrained after the June 2026 suspension
- High cost: $10/$50 per million tokens
- Mandatory 30-day data retention
Claude Opus 4.8: weaknesses
- Higher latency (58.7 tokens/s output)
- Premium pricing vs. median models
- No extended thinking budgets or top-p sampling
- Verbose output above median token usage
Claude Fable 5: best for
- Autonomous agentic workflows
- Long-horizon software engineering
- Complex knowledge work and research
- Multi-step tool-use with verifiable chain-of-thought
Claude Opus 4.8: best for
- Complex code generation and codebase migrations
- Agentic orchestration and long-form analysis
- Research synthesis with large contexts
- End-to-end project planning