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Claude Opus 4.5 vs DeepSeek-V4-Flash-0423

Claude Opus 4.5 and DeepSeek-V4-Flash-0423 are closely matched at 38.2 and 36.0 on the LLM Stats Score. DeepSeek-V4-Flash-0423 is 88.9x cheaper per token.

Anthropic · DeepSeek · Updated for 2026

Which is better?

Claude Opus 4.5 and DeepSeek-V4-Flash-0423 are closely matched on the overall LLM Stats Score at 38.2 and 36.0.

The models split the 4 individual benchmarks reported for both models evenly.

On price, DeepSeek-V4-Flash-0423 is roughly 88.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

DeepSeek-V4-Flash-0423 also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Opus 4.5

  • you want predictable pricing at $5.00/M input and $25.00/M output

Choose DeepSeek-V4-Flash-0423

  • cost matters — it's about 88.9x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Apr 2026
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Opus 4.5
Anthropic
DeepSeek-V4-Flash-0423
DeepSeek
Core performance indexes
LLM Stats Score
38.2
#74
36.0
#89
Reasoning
39.9
#60
37.0
#79
Coding
28.1
#65
26.6
#71
Agents
17.4
#81
15.6
#90
Cost, coverage & limits
Benchmark wins
2 of 4
2 of 4
Input price
$5.00 / M
$0.09 / M
Output price
$25.00 / M
$0.18 / M
Context window
200,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Opus 4.5
DeepSeek-V4-Flash-0423
Math
32.3#62
36.8#35
Tool use
20.7#55
15.4#92
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

11 reported for Claude Opus 4.5 · 19 for DeepSeek-V4-Flash-0423

4 shared

Claude Opus 4.5 outperforms in 2 benchmarks (SWE-Bench Verified, Terminal-Bench 2.0), while DeepSeek-V4-Flash-0423 is better at 2 benchmarks (GPQA, MCP Atlas).

Both models are evenly matched across the benchmarks.

Fri Oct 02 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

DeepSeek-V4-Flash-0423 costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 55.6x more expensive than DeepSeek-V4-Flash-0423 ($0.09/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 138.9x more expensive than DeepSeek-V4-Flash-0423 ($0.18/1M tokens).

In conclusion, Claude Opus 4.5 is more expensive than DeepSeek-V4-Flash-0423.*

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

Lowest available price from all providers
Fri Oct 02 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
DeepSeek
DeepSeek-V4-Flash-0423
Input tokens$0.09
Output tokens$0.18
Best providerDeepinfra
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

DeepSeek-V4-Flash-0423 accepts 1,048,576 input tokens compared to Claude Opus 4.5's 200,000 tokens. DeepSeek-V4-Flash-0423 can generate longer responses up to 1,048,576 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
DeepSeek
DeepSeek-V4-Flash-0423
Input1,048,576 tokens
Output1,048,576 tokens
Fri Oct 02 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Opus 4.5 supports multimodal inputs, whereas DeepSeek-V4-Flash-0423 does not.

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

Claude Opus 4.5

Text
Images
Audio
Video

DeepSeek-V4-Flash-0423

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 4.5 is licensed under a proprietary license, while DeepSeek-V4-Flash-0423 uses MIT.

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

Claude Opus 4.5

Proprietary

Closed source

DeepSeek-V4-Flash-0423

MIT

Open weights

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while DeepSeek-V4-Flash-0423 was released on 2026-04-23.

DeepSeek-V4-Flash-0423 is 5 months newer than Claude Opus 4.5.

Claude Opus 4.5

Nov 24, 2025

10 months ago

DeepSeek-V4-Flash-0423

Apr 23, 2026

5 months ago

5mo newer

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while DeepSeek-V4-Flash-0423's cutoff date is not specified.

We can confirm Claude Opus 4.5's training data extends to 2025-03-31, but cannot make a direct comparison without DeepSeek-V4-Flash-0423's cutoff date.

Claude Opus 4.5

Mar 2025

DeepSeek-V4-Flash-0423

—

Provider Availability

Claude Opus 4.5 is available from Anthropic. DeepSeek-V4-Flash-0423 is available from DeepInfra, Novita.

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

DeepSeek-V4-Flash-0423

deepinfra logo
Deepinfra
Input Price:Input: $0.09/1MOutput Price:Output: $0.18/1M
novita logo
Novita
Input Price:Input: $0.14/1MOutput Price:Output: $0.28/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Opus 4.5 and DeepSeek-V4-Flash-0423 side-by-side, then vote on the output you prefer.

Claude Opus 4.5
✓ Preferred
DeepSeek-V4-Flash-0423
Open in Playground

FAQ

Common questions about Claude Opus 4.5 vs DeepSeek-V4-Flash-0423.

Which is better, Claude Opus 4.5 or DeepSeek-V4-Flash-0423?

Claude Opus 4.5 and DeepSeek-V4-Flash-0423 are closely matched on the LLM Stats Score at 38.2 and 36.0. Claude Opus 4.5 is made by Anthropic and DeepSeek-V4-Flash-0423 is made by DeepSeek. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Opus 4.5 compare to DeepSeek-V4-Flash-0423 in benchmarks?

Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%. DeepSeek-V4-Flash-0423 scores CodeForces: 93.9%, HMMT Feb 26: 91.9%, LiveCodeBench: 88.4%, GPQA: 87.4%, MMLU-Pro: 86.4%.

Is Claude Opus 4.5 cheaper than DeepSeek-V4-Flash-0423?

DeepSeek-V4-Flash-0423 is 55.6x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. DeepSeek-V4-Flash-0423 costs $0.09/M input and $0.18/M output via deepinfra.

What are the context window sizes for Claude Opus 4.5 and DeepSeek-V4-Flash-0423?

Claude Opus 4.5 supports 200K tokens and DeepSeek-V4-Flash-0423 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 4.5 and DeepSeek-V4-Flash-0423?

Key differences include LLM Stats Score (38.2 vs 36.0), context window (200K vs 1.0M), input pricing ($5.00 vs $0.09/M), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and DeepSeek-V4-Flash-0423?

Claude Opus 4.5 is developed by Anthropic and DeepSeek-V4-Flash-0423 is developed by DeepSeek.

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