Pairwise benchmark snapshot · Aug 16, 2026

Claude Opus 4.8 vs Llama 3.1 405B benchmark

Name: Claude Opus 4.8 vs Llama 3.1 405B AI benchmark comparison
Creator: CompareLLM
License: https://creativecommons.org/licenses/by/4.0/

This page compares Claude Opus 4.8 (Anthropic) and Llama 3.1 405B (Meta) using the latest snapshots we have as of Aug 16, 2026. On preference Elo, Claude Opus 4.8 is ahead by 228 points (1,598 vs 1,370; seed-bootstrap (Aug 16, 2026)). On SWE-bench coding, Claude Opus 4.8 resolves 78.4% versus 58.4% (seed-bootstrap (Aug 16, 2026)). Claude Opus 4.8 streams faster (66 tok/s) while Llama 3.1 405B is the cheaper output token ($3.5/1M). Claude Opus 4.8 has the larger context window (1M tokens). Every cell below is a dated snapshot from a named public source — we do not invent missing scores, and we do not run SWE-bench ourselves.

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Anthropic

Claude Opus 4.8

Prior Opus generation still billed at $5/$25. Kept as a compare baseline against Opus 5.

Elo 1,598$25/1M out

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Quick vs:vs Claude Opus 4.5 vs Claude Opus 4.6 vs Claude Sonnet 4.5 vs Claude 3.7 Sonnet

Interactive Comparison Diagram

Matchup Breakdown

Tug-of-War Matchup Matrix

Category wins across intelligence, speed, and pricing efficiency.

Claude Opus 4.8 (8)vsLlama 3.1 405B (2)

Claude Opus 4.8: 8W (80%)Overall: Claude Opus 4.8Llama 3.1 405B: 2W (20%)

← Claude Opus 4.8Llama 3.1 405B →

Claude Opus 4.8 (5/5)

Intelligence & Reasoning

Preference Elo, Coding proficiency, SWE-bench & LiveBench accuracy

Preference Elo

1,598vs1,370

Coding Elo

1,604vs1,385

SWE-bench

78.4%vs58.4%

LiveBench

73.6%vs61.2%

GPQA Diamond

86.2%vs75.2%

Claude Opus 4.8: 5WLlama 3.1 405B: 0W

Claude Opus 4.8 (2/2)

Speed & Latency

Generation throughput and time to first token responsiveness

Output speed

66 tok/svs42 tok/s

Time to first token

330 msvs360 ms

Claude Opus 4.8: 2WLlama 3.1 405B: 0W

Llama 3.1 405B (2/3)

Pricing & Capacity

Cost per million tokens and max context window length

Output price

$25/1Mvs$3.5/1M

Input price

$5/1Mvs$1.25/1M

Context window

1Mvs128k

Claude Opus 4.8: 1WLlama 3.1 405B: 2W

Capability Matchup Radar

Multi-Dimensional Capability Radar

Each spoke is a skill. Farther from the center is better (0–100th percentile). Tap any dot to inspect details.

Tap any node to inspect

Percentile 0–100

Dimensional AdvantageClaude Opus 4.8 5/6

Preference Elo

Claude Opus 4.8

228 pts advantage

Throughput Speed

Claude Opus 4.8

24 tok/s faster

Price Efficiency

Llama 3.1 405B

$21.50/1M cheaper

Full Benchmark Score Matrix

—

Elo

High is better

+17%1,598

EloHigh is better

1,370

Code Elo

High is better

+16%1,604

Code EloHigh is better

1,385

LiveBench

High is better

+20%73.6%

LiveBenchHigh is better

61.2%

SWE-bench

High is better

+34%78.4%

SWE-benchHigh is better

58.4%

GPQA

High is better

+15%86.2%

GPQAHigh is better

75.2%

TTFT

Low is better

+9%330 ms

TTFTLow is better

360 ms

Speed

High is better

+57%66 tok/s

SpeedHigh is better

42 tok/s

In $

Low is better

$5/1M

In $Low is better

$1.25/1M+300%

Out $

Low is better

$25/1M

Out $Low is better

$3.5/1M+614%

Context

High is better

+681%1M

ContextHigh is better

128k

Interactive Simulator

Workload Cost & Savings Calculator

Simulate monthly production API costs based on published $/1M tokens.

Save up to 83% with Llama 3.1 405B

Monthly Volume50M tokens/mo

Quick Presets:

Token Ratio (In vs Out)70% In / 30% Out

RAG / Search (10% out)Coding / Chat (50% out)

Claude Opus 4.8$550.00 / mo

In: $175.00Out: $375.00

Llama 3.1 405B$96.25 / mo

In: $43.75Out: $52.50

Estimated Cost Delta

Llama 3.1 405B is estimated to save $453.75/month ($5,445/year).

Based on 50M tokens (30% gen)

Key Selection Recommendations

1
Claude Opus 4.8:Pick Claude Opus 4.8 when repo-level coding accuracy is the constraint.
2
Llama 3.1 405B:Pick Llama 3.1 405B when you are optimizing output cost.
3
Claude Opus 4.8:Pick Claude Opus 4.8 when time-to-first-token matters more than peak Elo.

Recommended Workload Routing

Repo / coding agentsClaude Opus 4.8

Higher SWE-bench (78.4%).

High-volume chatLlama 3.1 405B

Lower output list price ($3.5/1M).

Voice / low-latency UIClaude Opus 4.8

Lower TTFT (330 ms).

Long-document RAGClaude Opus 4.8

Larger window (1M).

Screenshots / visionClaude Opus 4.8

Claude Opus 4.8 is the side marked multimodal in the catalog.

Target Workload	Recommended Pick	Evaluation Rationale
Repo / coding agents	Claude Opus 4.8	Higher SWE-bench (78.4%).
High-volume chat	Llama 3.1 405B	Lower output list price ($3.5/1M).
Voice / low-latency UI	Claude Opus 4.8	Lower TTFT (330 ms).
Long-document RAG	Claude Opus 4.8	Larger window (1M).
Screenshots / vision	Claude Opus 4.8	Claude Opus 4.8 is the side marked multimodal in the catalog.

Related Editorial Dispatches & Benchmark Notes

View all news

launchJun 20, 2026

Keep Opus 4.8 on the board: a baseline, not a flagship

Opus 4.8 still bills $5/$25. We keep it so Opus 5 vs 4.8 is a real generation delta, not marketing.

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LIVE

Anthropic

Claude Opus 4.8

Elo 1,598

LiveBench73.6%

SWE-bench78.4%

Speed66 tok/s

Output cost$25/1M

Llama 3.1 405B

Elo 1,370

LiveBench61.2%

SWE-bench58.4%

Speed42 tok/s

Output cost$3.5/1M

Frequently Asked Questions

Which is better overall, Claude Opus 4.8 or Llama 3.1 405B?: Claude Opus 4.8 has the higher preference Elo in our latest snapshot (1,598). “Better” still depends on coding, price, and latency — see the table.
Which is better at coding, Claude Opus 4.8 or Llama 3.1 405B?: Claude Opus 4.8 leads SWE-bench at 78.4% vs 58.4%. SWE-bench is one harness, not your repo.
Which is cheaper to run in production?: Llama 3.1 405B output tokens are $3.5/1M versus $25/1M. Input prices and retry rates still move the real bill.
Which is faster, Claude Opus 4.8 or Llama 3.1 405B?: Claude Opus 4.8 has the lower time-to-first-token (330 ms vs 360 ms). Tokens/sec is a separate column if you care about long completions.
Which has the larger context window?: Claude Opus 4.8 accepts 1M tokens versus 128k.
Can I self-host either model?: Llama 3.1 405B is marked open-weights in our catalog. The other side is a closed API. Check the provider license before you ship weights.
Are these scores from CompareLLM’s own evals?: No. V1 aggregates public leaderboards (and optional first-party latency pings). Each cell names its source and date. Read /methodology.
What does preference Elo mean on this page?: Preference Elo is a crowd vote from LMArena / Arena. People see two hidden answers and pick the one they like more. The model that wins more often gets a higher Elo. That means people preferred it — not that it passed a school test. It is not SWE-bench, not accuracy, and not a number we invent. Claude Opus 4.8 and Llama 3.1 405B Elo cells are dated snapshots from the named source — we do not compute Arena ourselves.

Similar Head-to-Head Comparisons

All Claude Opus 4.8 matchups →|All Llama 3.1 405B matchups →

Claude Opus 4.8 vs Claude Opus 4.6 (previous opus)Claude Opus 4.8 vs Claude Opus 5 (next opus)Llama 3.1 405B vs Llama 3.1 70B (next llama)Claude Fable 5 vs Claude Opus 4.8 Claude Opus 4.5 vs Claude Opus 4.8 Claude Sonnet 5 vs Claude Opus 4.8

Claude Opus 4.8 vs Llama 3.1 405B benchmark

Interactive Comparison Diagram

Matchup Breakdown

Tug-of-War Matchup Matrix

Category wins across intelligence, speed, and pricing efficiency.

Claude Opus 4.8 (8)vsLlama 3.1 405B (2)

Claude Opus 4.8: 8W (80%)Overall: Claude Opus 4.8Llama 3.1 405B: 2W (20%)

← Claude Opus 4.8Llama 3.1 405B →

Claude Opus 4.8 (5/5)

Intelligence & Reasoning

Preference Elo, Coding proficiency, SWE-bench & LiveBench accuracy

Preference Elo

1,598vs1,370

Coding Elo

1,604vs1,385

SWE-bench

78.4%vs58.4%

LiveBench

73.6%vs61.2%

GPQA Diamond

86.2%vs75.2%

Claude Opus 4.8: 5WLlama 3.1 405B: 0W

Claude Opus 4.8 (2/2)

Speed & Latency

Generation throughput and time to first token responsiveness

Output speed

66 tok/svs42 tok/s

Time to first token

330 msvs360 ms

Claude Opus 4.8: 2WLlama 3.1 405B: 0W

Llama 3.1 405B (2/3)

Pricing & Capacity

Cost per million tokens and max context window length

Output price

$25/1Mvs$3.5/1M

Input price

$5/1Mvs$1.25/1M

Context window

1Mvs128k

Claude Opus 4.8: 1WLlama 3.1 405B: 2W

Recommended Workload Routing

Repo / coding agentsClaude Opus 4.8

Higher SWE-bench (78.4%).

High-volume chatLlama 3.1 405B

Lower output list price ($3.5/1M).

Voice / low-latency UIClaude Opus 4.8

Lower TTFT (330 ms).

Long-document RAGClaude Opus 4.8

Larger window (1M).

Screenshots / visionClaude Opus 4.8

Claude Opus 4.8 is the side marked multimodal in the catalog.

Target Workload	Recommended Pick	Evaluation Rationale
Repo / coding agents	Claude Opus 4.8	Higher SWE-bench (78.4%).
High-volume chat	Llama 3.1 405B	Lower output list price ($3.5/1M).
Voice / low-latency UI	Claude Opus 4.8	Lower TTFT (330 ms).
Long-document RAG	Claude Opus 4.8	Larger window (1M).
Screenshots / vision	Claude Opus 4.8	Claude Opus 4.8 is the side marked multimodal in the catalog.

Frequently Asked Questions

Which is better overall, Claude Opus 4.8 or Llama 3.1 405B?

Claude Opus 4.8 has the higher preference Elo in our latest snapshot (1,598). “Better” still depends on coding, price, and latency — see the table.

Which is better at coding, Claude Opus 4.8 or Llama 3.1 405B?

Claude Opus 4.8 leads SWE-bench at 78.4% vs 58.4%. SWE-bench is one harness, not your repo.

Which is cheaper to run in production?

Llama 3.1 405B output tokens are $3.5/1M versus $25/1M. Input prices and retry rates still move the real bill.

Which is faster, Claude Opus 4.8 or Llama 3.1 405B?

Claude Opus 4.8 has the lower time-to-first-token (330 ms vs 360 ms). Tokens/sec is a separate column if you care about long completions.

Which has the larger context window?

Claude Opus 4.8 accepts 1M tokens versus 128k.

Can I self-host either model?

Llama 3.1 405B is marked open-weights in our catalog. The other side is a closed API. Check the provider license before you ship weights.

Are these scores from CompareLLM’s own evals?

No. V1 aggregates public leaderboards (and optional first-party latency pings). Each cell names its source and date. Read /methodology.

What does preference Elo mean on this page?

Preference Elo is a crowd vote from LMArena / Arena. People see two hidden answers and pick the one they like more. The model that wins more often gets a higher Elo. That means people preferred it — not that it passed a school test. It is not SWE-bench, not accuracy, and not a number we invent. Claude Opus 4.8 and Llama 3.1 405B Elo cells are dated snapshots from the named source — we do not compute Arena ourselves.

Swap or Add Any Model to this Matchup

Interactive Comparison Diagram

Tug-of-War Matchup Matrix

Intelligence & Reasoning

Speed & Latency

Pricing & Capacity

Multi-Dimensional Capability Radar

Claude Opus 4.8

Claude Opus 4.8

Llama 3.1 405B

Full Benchmark Score Matrix

Workload Cost & Savings Calculator

Key Selection Recommendations

Recommended Workload Routing

Related Editorial Dispatches & Benchmark Notes

Keep Opus 4.8 on the board: a baseline, not a flagship

Cast Your Matchup Vote

Community Discussions (0)

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CompareLLM Matrix

Claude Opus 4.8

Llama 3.1 405B

Frequently Asked Questions

Related news

Similar Head-to-Head Comparisons

Swap or Add Any Model to this Matchup

Interactive Comparison Diagram

Tug-of-War Matchup Matrix

Intelligence & Reasoning

Speed & Latency

Pricing & Capacity

Multi-Dimensional Capability Radar

Claude Opus 4.8

Claude Opus 4.8

Llama 3.1 405B

Full Benchmark Score Matrix

Workload Cost & Savings Calculator

Key Selection Recommendations

Recommended Workload Routing

Related Editorial Dispatches & Benchmark Notes

Keep Opus 4.8 on the board: a baseline, not a flagship

Cast Your Matchup Vote

Community Discussions (0)

Share card

CompareLLM Matrix

Claude Opus 4.8

Llama 3.1 405B

Frequently Asked Questions

Related news

Similar Head-to-Head Comparisons