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Head-to-head comparison

Llama 3.1 8B Instruct vs Llama 4 Scout

Llama 3.1 8B Instruct (Meta) and Llama 4 Scout (Meta) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 22 September 2026

As of 22 September 2026, Llama 4 Scout holds the stronger ModelCap Index position (#171 vs #228); Llama 3.1 8B Instruct is 3.8× cheaper per output token ($0.08/1M vs $0.30/1M); and Llama 4 Scout offers the longer context window (1.3M vs 131K tokens).

Which should you choose?

Choose Llama 3.1 8B Instruct if…

  • API cost matters — $0.08/1M output tokens against $0.30/1M, about 3.8× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.05/1M against $0.10/1M.
  • you want provider choice — 5 listed API providers against 3.

Choose Llama 4 Scout if…

  • you want the stronger overall ModelCap Index position — #171 against #228 (30.2 vs 9.7 points).
  • you need the longer context window — 1.3M tokens against 131K.
  • Arena coding is your yardstick — 1362 against 1260.
  • BFCL V4 is your yardstick — 28.1 against 25.8.
  • you want the more recently listed model — Llama 4 Scout was listed 5 April 2025, Llama 3.1 8B Instruct 23 July 2024.

Llama 3.1 8B Instruct vs Llama 4 Scout: specs, pricing and context

Specification comparison of Llama 3.1 8B Instruct and Llama 4 Scout
FieldLlama 3.1 8B InstructMetaLlama 4 ScoutMeta
ModelCap Index position#228#171
Index score9.730.2
EvidenceMeasuredMeasured
Input price / 1M tokens$0.05$0.10
Output price / 1M tokens$0.08$0.30
Context window131K tokens1.3M tokens
Max output tokens118K16K
API providers listed53
Weight accessGated accessGated access
Input modalitiesTextText, Image
First listed23 July 20245 April 2025
PublisherMetaMeta

Evidence: 2 public benchmark observations across 2 boards · 3 public benchmark observations across 3 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: Llama 3.1 8B Instruct vs Llama 4 Scout

Public benchmark boards where Llama 3.1 8B Instruct or Llama 4 Scout has a published result
BoardLlama 3.1 8B InstructLlama 4 ScoutLeads
Arena codingArena (LMArena)12601252–126713621354–1371Llama 4 Scout
ARC-AGI-2ARC Prize Foundation—0.0%Only one result
BFCL V4UC Berkeley (Gorilla)25.8Prompt28.1Function callingLlama 4 Scout
AA τ²-Bench TelecomArtificial Analysis—15.5%tau2:telecom:dual-control:pass-at-1:3-repeats:source-model="Llama 4 Scout":reasoning=falseOnly one result
AA Humanity's Last ExamArtificial Analysis—3.8%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="Llama 4 Scout":reasoning=falseOnly one result

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

Llama 3.1 8B Instruct vs Llama 4 Scout: common questions

Is Llama 3.1 8B Instruct better than Llama 4 Scout?

Llama 4 Scout ranks higher on the ModelCap Index as of 22 September 2026: #171 against #228. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it. Their published uncertainty intervals do not overlap, but the aggregate Index does not predict performance on every task; compare the relevant benchmark configurations before choosing.

Is Llama 3.1 8B Instruct cheaper than Llama 4 Scout?

Llama 3.1 8B Instruct is cheaper on output tokens: $0.08/1M against $0.30/1M. Input tokens are $0.05/1M for Llama 3.1 8B Instruct and $0.10/1M for Llama 4 Scout. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens. For 1,000 requests with 2,000 input and 500 output tokens each (2M input + 0.5M output), the listed-rate estimate is $0.14 for Llama 3.1 8B Instruct versus $0.35 for Llama 4 Scout. Llama 3.1 8B Instruct costs 60.0% less in this scenario. This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the selected endpoint before budgeting.

Which has the bigger context window, Llama 3.1 8B Instruct or Llama 4 Scout?

Llama 4 Scout has the larger context window: 1.3M tokens against 131K.

Which is better for coding, Llama 3.1 8B Instruct or Llama 4 Scout?

Arena coding: Llama 3.1 8B Instruct 1260, Llama 4 Scout 1362 — Llama 4 Scout leads.

Are Llama 3.1 8B Instruct and Llama 4 Scout open-weight models?

Llama 3.1 8B Instruct: Gated access. Llama 4 Scout: Gated access. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.

Where can I run Llama 3.1 8B Instruct and Llama 4 Scout?

ModelCap currently lists 5 API providers for Llama 3.1 8B Instruct and 3 for Llama 4 Scout, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Llama 3.1 8B Instruct vs Llama 4 Scout comparison?

Every figure comes from the sealed ModelCap dataset published 22 September 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.

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