Comparisons

Meta Llama 3.1 405B Instruct vs Claude Sonnet 5

On provider list prices, Meta Llama 3.1 405B Instruct costs $3.50 per million input tokens against $3 for Claude Sonnet 5: effectively level. Output is $3.50 against $15 (4.3x). On Allocate both bill at list plus the 7% transaction fee.

Meta Llama 3.1 405B Instruct Claude Sonnet 5
LabMetaAnthropic
AccessOpen weightsAPI only
Context window4K tokens1M tokens
List price, input$3.5 / M tokens$3 / M tokens
List price, output$3.5 / M tokens$15 / M tokens
Cached inputn/an/a
LicenseLlama communityProprietary API
Fine-tunableYesNo

Specifications and provider list prices from the Allocate catalog, checked 2026-07-08. Billed price is list plus the 7% transaction fee.

What the numbers say

Take 1,000,000 requests a month at 1,200 input and 350 output tokens each. That workload costs $5,425 a month on Meta Llama 3.1 405B Instruct and $8,850 on Claude Sonnet 5 at list: a gap of $3,425, or 1.6x.

Claude Sonnet 5 reads 1M tokens per request against 4K for Meta Llama 3.1 405B Instruct, 244.1x the window. That decides which one can take whole documents without splitting them.

Claude Sonnet 5$3$15
Meta Llama 3.1 405B Instruct$3.50$3.50
InputOutput

Choose Meta Llama 3.1 405B Instruct for

  • Open weights you can fine-tune and own
Meta Llama 3.1 405B Instruct details

Choose Claude Sonnet 5 for

  • Judgment calls with policy context
  • Customer-facing writing
  • Review and escalation flows
Claude Sonnet 5 details

Common questions

Which is cheaper, Meta Llama 3.1 405B Instruct or Claude Sonnet 5?

Meta Llama 3.1 405B Instruct, on this workload shape. At list prices it is $3.50/$3.50 per million tokens in and out against $3/$15 for Claude Sonnet 5. Billed on Allocate: $3.75/$3.75 against $3.21/$16.05, list plus 7%.

Which has the bigger context window?

Claude Sonnet 5: 1,000,000 tokens (1M) against 4,096 (4K) for Meta Llama 3.1 405B Instruct.

Can I fine-tune Meta Llama 3.1 405B Instruct or Claude Sonnet 5?

Meta Llama 3.1 405B Instruct publishes open weights (Llama community) and can be fine-tuned on your own data. Claude Sonnet 5 is a closed model served over API; its weights are not available.

Related comparisons

Run the numbers on your workload

Or don’t choose. On Allocate a route name is the contract: point yours at one model today, swap to the other tomorrow, and compare them on your live traffic with per-token metering.