Claude Sonnet 4.5 vs DeepSeek V3.2

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

Claude Sonnet 4.5

Anthropic · Sep 2025

65.5

The model that made 30-hour autonomous coding sessions real — 77.2% SWE-bench Verified and a 1M-token context beta at $3/$15.

DeepSeek V3.2

DeepSeek · Sep 2025

68.4

The sparse-attention release that halved DeepSeek's already-lowest-in-class prices while keeping GPT-class quality.

The verdict

Claude Sonnet 4.5 and DeepSeek V3.2 split the 4 benchmarks they share evenly (2–2), so capability alone won't settle this one. On price the gap is dramatic: DeepSeek V3.2 works out roughly 19x cheaper per blended million tokens. Claude Sonnet 4.5 also takes 200K of context versus 128K for DeepSeek V3.2. And DeepSeek V3.2 is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.

Benchmark head-to-head 22

SWE-bench Verified
77.2%67.8%
Claude Sonnet 4.5DeepSeek V3.2
GPQA Diamond
83.4%79.9%
Claude Sonnet 4.5DeepSeek V3.2
AIME 2025
87%89.3%
Claude Sonnet 4.5DeepSeek V3.2
HLE
~17.3%~19.8%
Claude Sonnet 4.5DeepSeek V3.2

Specs & pricing

Claude Sonnet 4.5DeepSeek V3.2
modhub Index65.568.4
Input price / 1M$3$0.28
Output price / 1M$15$0.42
Context window200K128K
Max output64K64K
Open weightsnoyes (MIT)
Reasoning modelyesyes
Multimodal inputtext, imagetext
Knowledge cutoffJan 2025Jul 2025
ReleasedSep 2025Sep 2025
Example monthly cost*$52.50$3.43

* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.

Frequently asked questions

Which is better, Claude Sonnet 4.5 or DeepSeek V3.2?
Claude Sonnet 4.5 and DeepSeek V3.2 split the 4 benchmarks they share evenly (2–2), so capability alone won't settle this one. On price the gap is dramatic: DeepSeek V3.2 works out roughly 19x cheaper per blended million tokens. Claude Sonnet 4.5 also takes 200K of context versus 128K for DeepSeek V3.2. And DeepSeek V3.2 is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Which is cheaper, Claude Sonnet 4.5 or DeepSeek V3.2?
Claude Sonnet 4.5 costs $3/$15 per million input/output tokens, while DeepSeek V3.2 costs $0.28/$0.42. For a typical workload of 10M input and 1.5M output tokens per month, that's $52.50 versus $3.43.
Which model is better for coding, Claude Sonnet 4.5 or DeepSeek V3.2?
On SWE-bench Verified — the standard agentic-coding benchmark — Claude Sonnet 4.5 scores 77.2% versus 67.8% for DeepSeek V3.2, making Claude Sonnet 4.5 the stronger pick for coding agents.

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