Claude Opus 4 vs Llama 3.1 405B
Compare Claude Opus 4 and Llama 3.1 405B: pricing, performance, context window, latency, and best use cases. Side-by-side comparison on XALEN.
Updated 2026-05-21 · By Abhishek Raj · Our methodology
| Feature | Claude Opus 4 | Llama 3.1 405B |
|---|---|---|
| Category | Frontier | Open Source |
| Parameters | ~2T | 405B |
| Context Window | 200K | 128K |
| Input Price | $0.15/1M tokens | $0.08/1M tokens |
| Output Price | $0.75/1M tokens | $0.14/1M tokens |
| Latency | ~800ms | ~600ms |
Choose Claude Opus 4 when:
- ✓ Complex counseling
- ✓ Detailed chart analysis
- ✓ Enterprise reports
Deepest reasoning, Exceptional nuance, Best complex analysis
Choose Llama 3.1 405B when:
- ✓ Premium tasks
- ✓ Research
- ✓ Fine-tuning base
Largest open model, Highest open-source quality
Verdict: Claude Opus 4 vs Llama 3.1 405B
For cost efficiency, Llama 3.1 405B wins at $0.08/1M input tokens. For speed, Llama 3.1 405B is faster at ~600ms. Claude Opus 4 excels at Complex counseling while Llama 3.1 405B is better for Premium tasks. Both are available on XALEN through a single API — try them in the Playground to see which fits your workload.
Detailed Analysis
Pricing Comparison
Claude Opus 4 costs $0.15/1M input tokens and $0.75/1M output tokens. Llama 3.1 405B costs $0.08 input and $0.14 output. Llama 3.1 405B is 1.9x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.
Performance & Context
Claude Opus 4 has a 200K context window with ~800ms latency. Llama 3.1 405B offers 128K context at ~600ms. Claude Opus 4 has the larger context window.
Best For
Claude Opus 4 (Frontier) is optimized for: Complex counseling, Detailed chart analysis, Enterprise reports. Llama 3.1 405B (Open Source) works best for: Premium tasks, Research, Fine-tuning base.
Try Both on XALEN
Both models are available through XALEN's OpenAI-compatible API. Switch between them by changing the model parameter:
from xalen import XALEN
client = XALEN(api_key="xln_test_YOUR_KEY")
# Use Claude Opus 4
response_a = client.chat.completions.create(
model="claude-opus-4",
messages=[{"role": "user", "content": "Your question here"}]
)
# Use Llama 3.1 405B
response_b = client.chat.completions.create(
model="llama-3-1-405b",
messages=[{"role": "user", "content": "Your question here"}]
)Frequently Asked Questions
Which is better, Claude Opus 4 or Llama 3.1 405B?
Claude Opus 4 (Frontier, ~2T) offers Deepest reasoning. Llama 3.1 405B (Open Source, 405B) offers Largest open model. Choose Claude Opus 4 for Complex counseling or Llama 3.1 405B for Premium tasks.
How much does Claude Opus 4 cost vs Llama 3.1 405B?
Claude Opus 4: $0.15/1M input, $0.75/1M output. Llama 3.1 405B: $0.08/1M input, $0.14/1M output. Both available on XALEN with batch processing at 50% discount.
Can I use both models on XALEN?
Yes. XALEN provides 200+ models through a single OpenAI-compatible API. Switch between Claude Opus 4 and Llama 3.1 405B by changing the model parameter. No code changes needed.
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Last updated: 2026-05-21. Pricing and specifications may change. Check pricing page for latest rates.