Pairwise benchmark snapshot · Aug 1, 2026
In this head-to-head showdown, Claude Sonnet 4.5 delivers higher overall intelligence and human-preferred responses (Elo 1,524 vs 1,358), while Claude Sonnet 4.5 leads in SWE-bench software engineering benchmarks (70.1%), while DeepSeek R1 is more budget-friendly at $2.19/1M per 1M output tokens, while Claude Sonnet 4.5 provides faster response streaming (88 tok/s). Review the complete breakdown below to determine which model best fits your performance and budget requirements.
9 direct benchmark disciplines evaluated across capability, speed, and cost
Workhorse Anthropic model: most of Opus coding quality at a mid-tier price.
Open-weights reasoning model trained with large-scale RL.
Currently comparing Claude Sonnet 4.5 vs DeepSeek R1. 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 166 Arena Elo pts
88 tok/s
$2.19 / 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 Sonnet 4.5 | DeepSeek R1 | Advantage Delta |
|---|---|---|---|
| Preference Elo | +166 | ||
| Coding Elo | — | — | |
| LiveBench | +8.4% | ||
| SWE-bench | +4.9% | ||
| GPQA Diamond | +0.4% | ||
| Time to first token | +180 ms | ||
| Output speed | 88 tok/s | 62 tok/s | +26 tok/s |
| Input price | $0.55/1M | +$2.45/1M | |
| Output price | $2.19/1M | +$12.81/1M | |
| Context window | +72k |
Simulate monthly production API costs in USD (US Dollar).
DeepSeek R1 is estimated to save $277.90/month ($3,335/year).
Higher SWE-bench (70.1%).
Lower output list price ($2.19/1M).
Lower TTFT (240 ms).
Larger window (200k).
Claude Sonnet 4.5 is the side marked multimodal in the catalog.
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Claude Sonnet 4.5 | Higher SWE-bench (70.1%). |
| High-volume chat | DeepSeek R1 | Lower output list price ($2.19/1M). |
| Voice / low-latency UI | Claude Sonnet 4.5 | Lower TTFT (240 ms). |
| Long-document RAG | Claude Sonnet 4.5 | Larger window (200k). |
| Screenshots / vision | Claude Sonnet 4.5 | Claude Sonnet 4.5 is the side marked multimodal in the catalog. |
Most of Opus 4.5 coding at a mid-tier price. Sonnet 5 replaced it as the buy; 4.5 remains a compare baseline.
Jan 2025 reasoning model. Still searched. V4 Pro is the newer DeepSeek buy.
No comments posted on this matchup yet. Be the first to share an evaluation note!
Dynamic OpenGraph banner generated at /compare/claude-sonnet-4-5-vs-deepseek-r1/opengraph-image
Verified Head-to-Head Telemetry
