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Claude Opus 5 vs DeepSeek-V4.1-Flash

Claude Opus 5 and DeepSeek-V4.1-Flash are closely matched at 54.9 and 51.8 on the LLM Stats Score. DeepSeek-V4.1-Flash is 30.3x cheaper per token.

Anthropic · DeepSeek · Updated for 2026

Which is better?

Claude Opus 5 and DeepSeek-V4.1-Flash are closely matched on the overall LLM Stats Score at 54.9 and 51.8.

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

On price, DeepSeek-V4.1-Flash is roughly 30.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

DeepSeek-V4.1-Flash also accepts a larger context window (1,040,000 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 5

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

Choose DeepSeek-V4.1-Flash

  • cost matters — it's about 30.3x cheaper per token
  • you process long inputs — it offers a 1,040,000 token context window
  • you want the most recent training data — it shipped Sep 2026
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Opus 5
Anthropic
DeepSeek-V4.1-Flash
DeepSeek
Core performance indexes
LLM Stats Score
54.9
#5
51.8
#12
Reasoning
53.9
#4
48.9
#17
Coding
41.9
#9
44.4
#5
Agents
40.0
#7
41.3
#4
Cost, coverage & limits
Benchmark wins
2 of 4
2 of 4
Input price
$5.00 / M
$0.22 / M
Output price
$25.00 / M
$0.66 / M
Context window
1,000,000
1,040,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Opus 5
DeepSeek-V4.1-Flash
Vision
37.9#4
29.5#31
Tool use
27.9#21
35.1#2
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

13 reported for Claude Opus 5 · 20 for DeepSeek-V4.1-Flash

4 shared

Claude Opus 5 outperforms in 2 benchmarks (Humanity's Last Exam, Terminal-Bench 4.0), while DeepSeek-V4.1-Flash is better at 2 benchmarks (AutomationBench, DeepSWE 1.1).

Both models are evenly matched across the benchmarks.

Sat Sep 12 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

DeepSeek-V4.1-Flash costs less

For input processing, Claude Opus 5 ($5.00/1M tokens) is 22.7x more expensive than DeepSeek-V4.1-Flash ($0.22/1M tokens).

For output processing, Claude Opus 5 ($25.00/1M tokens) is 37.9x more expensive than DeepSeek-V4.1-Flash ($0.66/1M tokens).

In conclusion, Claude Opus 5 is more expensive than DeepSeek-V4.1-Flash.*

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

Lowest available price from all providers
Sat Sep 12 2026 • llm-stats.com
Anthropic
Claude Opus 5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
DeepSeek
DeepSeek-V4.1-Flash
Input tokens$0.22
Output tokens$0.66
Best providerFireworks
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

DeepSeek-V4.1-Flash accepts 1,040,000 input tokens compared to Claude Opus 5's 1,000,000 tokens. DeepSeek-V4.1-Flash can generate longer responses up to 393,216 tokens, while Claude Opus 5 is limited to 128,000 tokens.

Anthropic
Claude Opus 5
Input1,000,000 tokens
Output128,000 tokens
DeepSeek
DeepSeek-V4.1-Flash
Input1,040,000 tokens
Output393,216 tokens
Sat Sep 12 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Opus 5 and DeepSeek-V4.1-Flash support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Opus 5

Text
Images
Audio
Video

DeepSeek-V4.1-Flash

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 5 is licensed under a proprietary license, while DeepSeek-V4.1-Flash uses MIT.

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

Claude Opus 5

Proprietary

Closed source

DeepSeek-V4.1-Flash

MIT

Open weights

Release Timeline

When each model was launched

Claude Opus 5 was released on 2026-07-24, while DeepSeek-V4.1-Flash was released on 2026-09-10.

DeepSeek-V4.1-Flash is 2 months newer than Claude Opus 5.

Claude Opus 5

Jul 24, 2026

1 months ago

DeepSeek-V4.1-Flash

Sep 10, 2026

0 days ago

1mo newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude Opus 5 is available from Anthropic, DeepInfra. DeepSeek-V4.1-Flash is available from Fireworks, DeepInfra, DeepSeek, Novita.

Claude Opus 5

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

DeepSeek-V4.1-Flash

fireworks logo
Fireworks
Input Price:Input: $0.22/1MOutput Price:Output: $0.66/1M
deepinfra logo
Deepinfra
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
deepseek logo
DeepSeek
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
novita logo
Novita
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Opus 5 and DeepSeek-V4.1-Flash side-by-side, then vote on the output you prefer.

Claude Opus 5
✓ Preferred
DeepSeek-V4.1-Flash
Open in Playground

FAQ

Common questions about Claude Opus 5 vs DeepSeek-V4.1-Flash.

Which is better, Claude Opus 5 or DeepSeek-V4.1-Flash?

Claude Opus 5 and DeepSeek-V4.1-Flash are closely matched on the LLM Stats Score at 54.9 and 51.8. Claude Opus 5 is made by Anthropic and DeepSeek-V4.1-Flash 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 5 compare to DeepSeek-V4.1-Flash in benchmarks?

Claude Opus 5 scores BrowseComp: 90.8%, BioMysteryBench: 90.1%, OSWorld 2.0: 70.6%, DeepSWE 1.1: 68.8%, Humanity's Last Exam: 64.7%. DeepSeek-V4.1-Flash scores CodeForces: 100.0%, GPQA: 90.9%, Terminal-Bench 2.1: 90.6%, BabyVision: 89.6%, CyberGym: 88.1%.

Is Claude Opus 5 cheaper than DeepSeek-V4.1-Flash?

DeepSeek-V4.1-Flash is 22.7x cheaper for input tokens. Claude Opus 5 costs $5.00/M input and $25.00/M output via anthropic. DeepSeek-V4.1-Flash costs $0.22/M input and $0.66/M output via fireworks.

What are the context window sizes for Claude Opus 5 and DeepSeek-V4.1-Flash?

Claude Opus 5 supports 1.0M tokens and DeepSeek-V4.1-Flash 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 5 and DeepSeek-V4.1-Flash?

Key differences include LLM Stats Score (54.9 vs 51.8), context window (1.0M vs 1.0M), input pricing ($5.00 vs $0.22/M), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 5 and DeepSeek-V4.1-Flash?

Claude Opus 5 is developed by Anthropic and DeepSeek-V4.1-Flash is developed by DeepSeek.

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