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DeepSeek-V4.1-Flash vs Llama 3.1 405B Instruct

DeepSeek-V4.1-Flash leads the LLM Stats Score 50.7 to 14.7. DeepSeek-V4.1-Flash is 2.7x cheaper per token.

DeepSeek · Meta · Updated for 2026

Which is better?

DeepSeek-V4.1-Flash leads the overall LLM Stats Score 50.7 to 14.7, ranking #17 overall.

In the 1 individual benchmarks reported for both models, DeepSeek-V4.1-Flash wins 1; this is a narrower head-to-head signal than the composite indexes.

On price, DeepSeek-V4.1-Flash is roughly 2.7x 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 DeepSeek-V4.1-Flash

  • overall performance matters — it scores 50.7 and ranks #17 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • cost matters — it's about 2.7x 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

Choose Llama 3.1 405B Instruct

  • you want predictable pricing at $0.89/M input and $0.89/M output

At a glance

The differences that matter most.

Core performance indexes
50.7
#17
14.7
#249
48.5
#19
13.8
#249
41.5
#9
11.5
#167
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
$0.22 / M
$0.89 / M
Output price
$0.66 / M
$0.89 / M
Context window
1,040,000
128,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
DeepSeek-V4.1-Flash
Llama 3.1 405B Instruct
34.8#47
19.3#174
32.4#4
30.8#9
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

20 reported for DeepSeek-V4.1-Flash · 18 for Llama 3.1 405B Instruct

1 shared

DeepSeek-V4.1-Flash outperforms in 1 benchmarks (GPQA), while Llama 3.1 405B Instruct is better at 0 benchmarks.

DeepSeek-V4.1-Flash significantly outperforms across most benchmarks.

Wed Oct 14 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, DeepSeek-V4.1-Flash ($0.22/1M tokens) is 4.0x cheaper than Llama 3.1 405B Instruct ($0.89/1M tokens).

For output processing, DeepSeek-V4.1-Flash ($0.66/1M tokens) is 1.3x cheaper than Llama 3.1 405B Instruct ($0.89/1M tokens).

In conclusion, Llama 3.1 405B Instruct is more expensive than DeepSeek-V4.1-Flash.*

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

Lowest available price from all providers
Wed Oct 14 2026 • llm-stats.com
DeepSeek
DeepSeek-V4.1-Flash
Input tokens$0.22
Output tokens$0.66
Best providerFireworks
Meta
Llama 3.1 405B Instruct
Input tokens$0.89
Output tokens$0.89
Best providerLambda
Notice missing or incorrect data?

Model Size

Parameter count comparison

358.2B diff

DeepSeek-V4.1-Flash has 358.2B more parameters than Llama 3.1 405B Instruct, making it 88.4% larger.

DeepSeek
DeepSeek-V4.1-Flash
763.2Bparameters
Meta
Llama 3.1 405B Instruct
405.0Bparameters
763.2B
DeepSeek-V4.1-Flash
405.0B
Llama 3.1 405B Instruct

Context Window

Maximum input and output token capacity

DeepSeek-V4.1-Flash accepts 1,040,000 input tokens compared to Llama 3.1 405B Instruct's 128,000 tokens. DeepSeek-V4.1-Flash can generate longer responses up to 393,216 tokens, while Llama 3.1 405B Instruct is limited to 128,000 tokens.

DeepSeek
DeepSeek-V4.1-Flash
Input1,040,000 tokens
Output393,216 tokens
Meta
Llama 3.1 405B Instruct
Input128,000 tokens
Output128,000 tokens
Wed Oct 14 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

DeepSeek-V4.1-Flash supports multimodal inputs, whereas Llama 3.1 405B Instruct does not.

DeepSeek-V4.1-Flash can handle both text and other forms of data like images, making it suitable for multimodal applications.

DeepSeek-V4.1-Flash

Text
Images
Audio
Video

Llama 3.1 405B Instruct

Text
Images
Audio
Video

License

Usage and distribution terms

DeepSeek-V4.1-Flash is licensed under MIT, while Llama 3.1 405B Instruct uses Llama 3.1 Community License.

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

DeepSeek-V4.1-Flash

MIT

Open weights

Llama 3.1 405B Instruct

Llama 3.1 Community License

Open weights

Release Timeline

When each model was launched

DeepSeek-V4.1-Flash was released on 2026-09-10, while Llama 3.1 405B Instruct was released on 2024-07-23.

DeepSeek-V4.1-Flash is 26 months newer than Llama 3.1 405B Instruct.

DeepSeek-V4.1-Flash

Sep 10, 2026

1 months ago

2.1yr newer
Llama 3.1 405B Instruct

Jul 23, 2024

2.2 years ago

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

DeepSeek-V4.1-Flash is available from Fireworks, DeepInfra, DeepSeek, Novita. Llama 3.1 405B Instruct is available from Lambda, DeepInfra, Fireworks, Bedrock, Together, Hyperbolic, Google, Replicate.

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

Llama 3.1 405B Instruct

lambda logo
Lambda
Input Price:Input: $0.89/1MOutput Price:Output: $0.89/1M
deepinfra logo
Deepinfra
Input Price:Input: $1.79/1MOutput Price:Output: $1.79/1M
fireworks logo
Fireworks
Input Price:Input: $3.00/1MOutput Price:Output: $3.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $3.00/1MOutput Price:Output: $3.00/1M
together logo
Together
Input Price:Input: $3.50/1MOutput Price:Output: $3.50/1M
hyperbolic logo
Hyperbolic
Input Price:Input: $4.00/1MOutput Price:Output: $4.00/1M
google logo
Google
Input Price:Input: $5.00/1MOutput Price:Output: $16.00/1M
replicate logo
Replicate
Input Price:Input: $9.50/1MOutput Price:Output: $9.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against DeepSeek-V4.1-Flash and Llama 3.1 405B Instruct side-by-side, then vote on the output you prefer.

DeepSeek-V4.1-Flash
✓ Preferred
Llama 3.1 405B Instruct
Open in Playground

FAQ

Common questions about DeepSeek-V4.1-Flash vs Llama 3.1 405B Instruct.

Which is better, DeepSeek-V4.1-Flash or Llama 3.1 405B Instruct?

DeepSeek-V4.1-Flash leads the LLM Stats Score 50.7 to 14.7. DeepSeek-V4.1-Flash is made by DeepSeek and Llama 3.1 405B Instruct is made by Meta. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does DeepSeek-V4.1-Flash compare to Llama 3.1 405B Instruct in benchmarks?

DeepSeek-V4.1-Flash scores CodeForces: 100.0%, GPQA: 90.9%, Terminal-Bench 2.1: 90.6%, BabyVision: 89.6%, CyberGym: 88.1%. Llama 3.1 405B Instruct scores ARC-C: 96.9%, GSM8k: 96.8%, API-Bank: 92.0%, Multilingual MGSM (CoT): 91.6%, HumanEval: 89.0%.

Is DeepSeek-V4.1-Flash cheaper than Llama 3.1 405B Instruct?

DeepSeek-V4.1-Flash is 4.0x cheaper for input tokens. DeepSeek-V4.1-Flash costs $0.22/M input and $0.66/M output via fireworks. Llama 3.1 405B Instruct costs $0.89/M input and $0.89/M output via lambda.

What are the context window sizes for DeepSeek-V4.1-Flash and Llama 3.1 405B Instruct?

DeepSeek-V4.1-Flash supports 1.0M tokens and Llama 3.1 405B Instruct supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between DeepSeek-V4.1-Flash and Llama 3.1 405B Instruct?

Key differences include LLM Stats Score (50.7 vs 14.7), context window (1.0M vs 128K), input pricing ($0.22 vs $0.89/M), multimodal support (yes vs no), licensing (MIT vs Llama 3.1 Community License). See the full comparison above for benchmark-by-benchmark results.

Who makes DeepSeek-V4.1-Flash and Llama 3.1 405B Instruct?

DeepSeek-V4.1-Flash is developed by DeepSeek and Llama 3.1 405B Instruct is developed by Meta.