Compare / head-to-head
Claude Fable 5.1vsClaude Opus 5
Claude Fable 5.1 leads 8 of 8 shared benchmarks. Claude Opus 5 is 2x cheaper per token. Both offer a 1M-token context window.
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
8 – 0
Claude Fable 5.1 leads
Cheaper per token
Claude Opus 5
2x cheaper, input + output
Larger context
Tie
both 1M tokens
Provider uptime (30d)
100%
Anthropic
Claude Fable 5.1
Anthropic · released 2026-09-01
textvision
Claude Opus 5
Anthropic · released 2026-07-24
textvision
Quality
Benchmark matrix
8 shared · 0 only Claude Fable 5.1 · 1 only Claude Opus 5| Benchmark | Claude Fable 5.1 | Claude Opus 5 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 8 | ||||
| Humanity's Last Exam (no tools) | 60.9% ↗ | 56.6% ↗ | +4.3 pt | Claude Fable 5.1 |
| CursorBench 3.2.0 | 73.4% ↗ | 70% ↗ | +3.4 pt | Claude Fable 5.1 |
| FrontierMath Tier 4 v2 (Epoch AI run) | 87.8% ↗epoch | 73.2% ↗epoch | +14.6 pt | Claude Fable 5.1 |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 90.2% ↗epoch | 85.6% ↗epoch | +4.6 pt | Claude Fable 5.1 |
| GDPval-AA v2 | 1853 ↗ | 1824 ↗ | +29 | Claude Fable 5.1 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 100% ↗epoch | 98.9% ↗epoch | +1.1 pt | Claude Fable 5.1 |
| SimpleQA Verified | 70.8% ↗epoch | 59.9% ↗epoch | +10.9 pt | Claude Fable 5.1 |
| Terminal-Bench Science 0.1 | 52.6% ↗ | 29% ↗ | +23.6 pt | Claude Fable 5.1 |
| Only Claude Fable 5.1 reports · 0 | ||||
| Claude Fable 5.1 reports nothing Claude Opus 5 does not. | ||||
| Only Claude Opus 5 reports · 1 | ||||
| GPQA Diamond | not reported | 93.9% ↗epoch | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Fable 5.1 minus Claude Opus 5 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | Claude Fable 5.1 | Claude Opus 5 | Edge |
|---|---|---|---|
| Context window | 1M tokens | 1M tokens | Tie |
| Max output | 128K tokens | 128K tokens | Tie |
| Input price / 1M | $10 ↗ | $5 ↗ | Claude Opus 5 |
| Output price / 1M | $50 ↗ | $25 ↗ | Claude Opus 5 |
| Cached input / 1M | $0.25 ↗ | $0.5 ↗ | Claude Fable 5.1 |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $60 | $30 | Claude Opus 5 |
| Modalities | text · vision | text · vision | Tie |
| Released | 2026-09-01 | 2026-07-24 | — |
| Cited benchmark scores | 8 | 9 | — |
Reliability
Anthropic status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
Claude Fable 5.1 vs …
Models sharing the most benchmarksMore matchups
Claude Opus 5 vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run Claude Fable 5.1 and Claude Opus 5 on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.