Pairwise benchmark snapshot · Aug 16, 2026
This page compares Claude Opus 4.5 (Anthropic) and Claude Sonnet 4.5 (Anthropic) using the latest snapshots we have as of Aug 16, 2026. On preference Elo, Claude Opus 4.5 is ahead by 44 points (1,568 vs 1,524; seed-bootstrap (Aug 1, 2026)). On SWE-bench coding, Claude Opus 4.5 resolves 76.8% versus 70.1% (seed-bootstrap (Aug 1, 2026)). Claude Sonnet 4.5 streams faster (88 tok/s) while Claude Sonnet 4.5 is the cheaper output token ($15/1M). Claude Sonnet 4.5 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 Opus 4.5Anthropic frontier coding and computer-use model. SWE-bench leader on the official mini-SWE-agent harness in the Feb 2026 refresh.
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.
44 pts advantage
26 tok/s faster
$10.00/1M cheaper
Simulate monthly production API costs based on published $/1M tokens.
Claude Sonnet 4.5 is estimated to save $220.00/month ($2,640/year).
Higher SWE-bench (76.8%).
Lower output list price ($15/1M).
Lower TTFT (240 ms).
Larger window (1M).
Both accept images. Defaulting to the higher-Elo side (Claude Opus 4.5).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Claude Opus 4.5 | Higher SWE-bench (76.8%). |
| 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 Sonnet 4.5 | Larger window (1M). |
| Screenshots / vision | Claude Opus 4.5 | Both accept images. Defaulting to the higher-Elo side (Claude Opus 4.5). |
The Feb refresh made 4.5 a coding reference. Newer Opus SKUs exist; this row stays as the dated harness point.
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-opus-4-5-vs-claude-sonnet-4-5/opengraph-image for crawlers.
Verified head-to-head card
