Model Comparison

Claude Sonnet 4.5 vs DeepSeek-V3.1Which is better in 2026?

Claude Sonnet 4.5 significantly outperforms across most benchmarks. DeepSeek-V3.1 is 13.3x cheaper per token.

Verdict: Claude Sonnet 4.5 vs DeepSeek-V3.1 — which is better?

Claude Sonnet 4.5 (by Anthropic) and DeepSeek-V3.1 (by DeepSeek) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Claude Sonnet 4.5 outperforms in 3 benchmarks (AIME 2025, GPQA, Terminal-Bench), while DeepSeek-V3.1 is better at 0 benchmarks. Claude Sonnet 4.5 significantly outperforms across most benchmarks.

On price, DeepSeek-V3.1 is roughly 13.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Sonnet 4.5 also accepts a larger context window (200,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Sonnet 4.5 if…

  • you want the strongest raw capability — it leads on 3 of 3 shared benchmarks
  • you process long inputs — it offers a 200,000 token context window
  • you want the most recent training data — it shipped Sep 2025

Choose DeepSeek-V3.1 if…

  • cost matters — it's about 13.3x cheaper per token
  • you need open weights you can self-host or fine-tune
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Performance Benchmarks

Comparative analysis across standard metrics

3 benchmarks

Claude Sonnet 4.5 outperforms in 3 benchmarks (AIME 2025, GPQA, Terminal-Bench), while DeepSeek-V3.1 is better at 0 benchmarks.

Claude Sonnet 4.5 significantly outperforms across most benchmarks.

Sun Jun 07 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

DeepSeek-V3.1 costs less

For input processing, Claude Sonnet 4.5 ($3.00/1M tokens) is 11.1x more expensive than DeepSeek-V3.1 ($0.27/1M tokens).

For output processing, Claude Sonnet 4.5 ($15.00/1M tokens) is 15.0x more expensive than DeepSeek-V3.1 ($1.00/1M tokens).

In conclusion, Claude Sonnet 4.5 is more expensive than DeepSeek-V3.1.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Sun Jun 07 2026 • llm-stats.com
Anthropic
Claude Sonnet 4.5
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
DeepSeek
DeepSeek-V3.1
Input tokens$0.27
Output tokens$1.00
Best providerDeepinfra
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude Sonnet 4.5 accepts 200,000 input tokens compared to DeepSeek-V3.1's 163,840 tokens. DeepSeek-V3.1 can generate longer responses up to 163,840 tokens, while Claude Sonnet 4.5 is limited to 64,000 tokens.

Anthropic
Claude Sonnet 4.5
Input200,000 tokens
Output64,000 tokens
DeepSeek
DeepSeek-V3.1
Input163,840 tokens
Output163,840 tokens
Sun Jun 07 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude Sonnet 4.5 supports multimodal inputs, whereas DeepSeek-V3.1 does not.

Claude Sonnet 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Sonnet 4.5

Text
Images
Audio
Video

DeepSeek-V3.1

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Sonnet 4.5 is licensed under a proprietary license, while DeepSeek-V3.1 uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Sonnet 4.5

Proprietary

Closed source

DeepSeek-V3.1

MIT

Open weights

Release Timeline

When each model was launched

Claude Sonnet 4.5 was released on 2025-09-29, while DeepSeek-V3.1 was released on 2025-01-10.

Claude Sonnet 4.5 is 9 months newer than DeepSeek-V3.1.

Claude Sonnet 4.5

Sep 29, 2025

8 months ago

8mo newer
DeepSeek-V3.1

Jan 10, 2025

1.4 years ago

Knowledge Cutoff

When training data ends

Claude Sonnet 4.5 has a documented knowledge cutoff of 2025-01-31, while DeepSeek-V3.1's cutoff date is not specified.

We can confirm Claude Sonnet 4.5's training data extends to 2025-01-31, but cannot make a direct comparison without DeepSeek-V3.1's cutoff date.

Claude Sonnet 4.5

Jan 2025

DeepSeek-V3.1

—

Provider Availability

Claude Sonnet 4.5 is available from Anthropic. DeepSeek-V3.1 is available from DeepInfra, Novita.

Claude Sonnet 4.5

anthropic logo
Anthropic
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

DeepSeek-V3.1

deepinfra logo
Deepinfra
Input Price:Input: $0.27/1MOutput Price:Output: $1.00/1M
novita logo
Novita
Input Price:Input: $0.27/1MOutput Price:Output: $1.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Supports multimodal inputs
Higher AIME 2025 score (87.0% vs 49.8%)
Higher GPQA score (83.4% vs 74.9%)
Higher Terminal-Bench score (50.0% vs 31.3%)
DeepSeek
Less expensive input tokens
Less expensive output tokens
Has open weights

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Sonnet 4.5
DeepSeek
DeepSeek-V3.1

FAQ

Common questions about Claude Sonnet 4.5 vs DeepSeek-V3.1.

Which is better, Claude Sonnet 4.5 or DeepSeek-V3.1?

Claude Sonnet 4.5 significantly outperforms across most benchmarks. Claude Sonnet 4.5 is made by Anthropic and DeepSeek-V3.1 is made by DeepSeek. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Sonnet 4.5 compare to DeepSeek-V3.1 in benchmarks?

Claude Sonnet 4.5 scores MMMLU: 89.1%, AIME 2025: 87.0%, TAU-bench Retail: 86.2%, GPQA: 83.4%, MMMUval: 77.8%. DeepSeek-V3.1 scores SimpleQA: 93.4%, MMLU-Redux: 91.8%, MMLU-Pro: 83.7%, GPQA: 74.9%, CodeForces: 69.7%.

Is Claude Sonnet 4.5 cheaper than DeepSeek-V3.1?

DeepSeek-V3.1 is 11.1x cheaper for input tokens. Claude Sonnet 4.5 costs $3.00/M input and $15.00/M output via anthropic. DeepSeek-V3.1 costs $0.27/M input and $1.00/M output via deepinfra.

What are the context window sizes for Claude Sonnet 4.5 and DeepSeek-V3.1?

Claude Sonnet 4.5 supports 200K tokens and DeepSeek-V3.1 supports 164K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Sonnet 4.5 and DeepSeek-V3.1?

Key differences include context window (200K vs 164K), input pricing ($3.00 vs $0.27/M), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 4.5 and DeepSeek-V3.1?

Claude Sonnet 4.5 is developed by Anthropic and DeepSeek-V3.1 is developed by DeepSeek.

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