Question 1

What does this Llama 3.1 405B vs Llama 4 Scout 17B Instruct comparison cover?

Accepted Answer

It brings together documented inputs and outputs, token limits, deployment terms and available pricing. When both models have source-linked, verified results on a shared benchmark, those results are shown with their individual sources. The comparison is a starting point for evaluating your own workload.

Question 2

Which is cheaper: Llama 3.1 405B or Llama 4 Scout 17B Instruct?

Accepted Answer

The available pricing does not establish a comparable input and output token rate for both models. Check the billing unit and selected host in each profile. Images, speech, video and local inference can have different cost structures.

Question 3

Which has the larger context window: Llama 3.1 405B or Llama 4 Scout 17B Instruct?

Accepted Answer

Llama 3.1 405B lists 128K tokens and Llama 4 Scout 17B Instruct lists 10M. Llama 4 Scout 17B Instruct therefore has the larger recorded context window, but capacity alone is not a quality score.

Question 4

Which is faster: Llama 3.1 405B or Llama 4 Scout 17B Instruct?

Accepted Answer

There is no matched speed measurement for both models with the same source, host, region and date. Test the same prompts at your expected concurrency and measure time to the first useful response as well as complete task time.

Question 5

What input and output types do Llama 3.1 405B and Llama 4 Scout 17B Instruct support?

Accepted Answer

Llama 3.1 405B records text input and text output. Llama 4 Scout 17B Instruct records text, image input and text output. “Not documented” means the current source record is incomplete; it does not prove that a modality is unsupported.

Question 6

Should I choose Llama 3.1 405B or Llama 4 Scout 17B Instruct?

Accepted Answer

Consider Llama 4 Scout 17B Instruct if you need larger context or larger maximum output. Test both on the same representative examples and judge the output against your acceptance criteria. Include tool failures, retries and the time to a completed task.

Specification	Llama 3.1 405B	Llama 4 Scout 17B Instruct
Provider	Meta	Meta
Listed pricing route	Meta	Meta
Model family	Llama 3.1	llama
Accepted inputs	text	text, image
Produced outputs	text	text
Context window	128K	10MHigher
Max output	4.1K	16.38KHigher
Input price / 1M	$3.50	$0.18
Output price / 1M	$3.50	$0.59
Output speed	30 t/s	—
Time to first token	0.70s	—
Reasoning mode	Not documented	Not documented
Tool calling	Documented	Documented
Image input	Not documented	Documented
Audio input	Not documented	Not documented
Structured output	Documented	Not documented
License	Llama 3.1 Community	Open weights

Llama 3.1 405B vs Llama 4 Scout 17B Instruct

Llama 3.1 405B

Llama 4 Scout 17B Instruct

Key differences

Pricing, limits and capabilities

Which model should you choose?

Documentation and model profiles

Questions people ask

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