Pairwise benchmark snapshot · Aug 16, 2026
This page compares Claude Fable 5 (Anthropic) and Claude Sonnet 4.5 (Anthropic) using the latest snapshots we have as of Aug 16, 2026. On preference Elo, Claude Fable 5 is ahead by 92 points (1,616 vs 1,524; seed-bootstrap (Aug 16, 2026)). On SWE-bench coding, Claude Fable 5 resolves 80% versus 70.1% (seed-bootstrap (Aug 16, 2026)). Claude Sonnet 4.5 streams faster (88 tok/s) while Claude Sonnet 4.5 is the cheaper output token ($15/1M). Claude Fable 5 has the larger context window (1M tokens). Every cell below is a dated snapshot from a named public source — we do not invent missing scores, and we do not run SWE-bench ourselves.
Anthropic
Claude Fable 5Anthropic top-tier long-horizon model. Official API $10/$50 per 1M tokens (Claude Platform pricing, Aug 2026).
Anthropic
Claude Sonnet 4.5Workhorse Anthropic model: most of Opus coding quality at a mid-tier price.
Instant pairwise benchmark recalculation across 400+ LLMs
Category wins across intelligence, speed, and pricing efficiency.
Preference Elo, Coding proficiency, SWE-bench & LiveBench accuracy
Generation throughput and time to first token responsiveness
Cost per million tokens and max context window length
Each spoke is a skill. Farther from the center is better (0–100th percentile). Tap any dot to inspect details.
92 pts advantage
30 tok/s faster
$35.00/1M cheaper
Simulate monthly production API costs based on published $/1M tokens.
Claude Sonnet 4.5 is estimated to save $770.00/month ($9,240/year).
Higher SWE-bench (80%).
Lower output list price ($15/1M).
Lower TTFT (240 ms).
Larger window (1M).
Both accept images. Defaulting to the higher-Elo side (Claude Fable 5).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Claude Fable 5 | Higher SWE-bench (80%). |
| High-volume chat | Claude Sonnet 4.5 | Lower output list price ($15/1M). |
| Voice / low-latency UI | Claude Sonnet 4.5 | Lower TTFT (240 ms). |
| Long-document RAG | Claude Fable 5 | Larger window (1M). |
| Screenshots / vision | Claude Fable 5 | Both accept images. Defaulting to the higher-Elo side (Claude Fable 5). |
Fable 5 is not Sonnet with extra adjectives. It is the expensive long-horizon row. Read SWE-bench and output price together.
Most of Opus 4.5 coding at a mid-tier price. Sonnet 5 replaced it as the buy; 4.5 remains a compare baseline.
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The real PNG is generated at /compare/claude-fable-5-vs-claude-sonnet-4-5/opengraph-image for crawlers.
Verified head-to-head card
