Pairwise benchmark snapshot · Aug 16, 2026
In this head-to-head showdown, Claude Opus 4.5 delivers higher overall intelligence and human-preferred responses (Elo 1,568 vs 1,556), while Claude Opus 4.5 leads in SWE-bench software engineering benchmarks (76.8%), while Claude Sonnet 5 is more budget-friendly at $10/1M per 1M output tokens. Review the complete breakdown below to determine which model best fits your performance and budget requirements.
10 direct benchmark disciplines evaluated across capability, speed, and cost
Anthropic frontier coding and computer-use model. SWE-bench leader on the official mini-SWE-agent harness in the Feb 2026 refresh.
Anthropic workhorse. Official $2/$10 per 1M tokens made permanent on Aug 10 2026.
Currently comparing Claude Opus 4.5 vs Claude Sonnet 5. Alternative family tiers available.
Simulate accuracy gains vs added response time & token cost
Reasoning models “think before answering” by generating internal reasoning tokens. Higher effort improves math, coding, and logic accuracy, but increases response delay and token costs.
Δ 12 Arena Elo pts
118 tok/s
$10 / 1M output
Relative percentile scores computed across all active models in the benchmark catalog.
Comparing top Western standard models with China's leading frontier rival across 6 skill dimensions. Tap any spoke or dot to inspect.
Category wins across reasoning intelligence, generation speed, and token cost.
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
| Benchmark | Claude Opus 4.5 | Claude Sonnet 5 | Advantage Delta |
|---|---|---|---|
| Preference Elo | +12 | ||
| Coding Elo | +12 | ||
| LiveBench | +0.8% | ||
| SWE-bench | +3% | ||
| GPQA Diamond | +1.3% | ||
| Time to first token | +205 ms | ||
| Output speed | 62 tok/s | 118 tok/s | +56 tok/s |
| Input price | +$13/1M | ||
| Output price | +$65/1M | ||
| Context window | +800k |
Simulate monthly production API costs in USD (US Dollar).
Claude Sonnet 5 is estimated to save $1,430.00/month ($17,160/year).
Higher SWE-bench (76.8%).
Lower output list price ($10/1M).
Lower TTFT (175 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 5 | Lower output list price ($10/1M). |
| Voice / low-latency UI | Claude Sonnet 5 | Lower TTFT (175 ms). |
| Long-document RAG | Claude Sonnet 5 | Larger window (1M). |
| Screenshots / vision | Claude Opus 4.5 | Both accept images. Defaulting to the higher-Elo side (Claude Opus 4.5). |
Usually Sonnet 5 vs Opus 5. Coding delta versus output $/1M. The workhorse question.
Aug 10 2026 made the $2/$10 list permanent. Sonnet is the default Claude unless the repo is actually on fire.
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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Verified Head-to-Head Telemetry
compare · Aug 10, 2026
Sonnet vs Opus in 2026: same family, different invoice
price · Aug 10, 2026
Claude Sonnet 5 at $2/$10: the 2026 Anthropic workhorse
launch · Feb 20, 2026
Claude Opus 4.5 and the Feb 2026 SWE-bench row we still cite
launch · Feb 18, 2026
Claude Sonnet 4.5 is the previous workhorse — still a valid vs baseline