Llama 3.1 405B vs FLUX.1 Dev

Compare Llama 3.1 405B and FLUX.1 Dev: pricing, performance, context window, latency, and best use cases. Side-by-side comparison on XALEN.

Updated 2026-05-21 · By Abhishek Raj · Our methodology

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Feature Llama 3.1 405B FLUX.1 Dev
CategoryOpen SourceImage
Parameters405B12B
Context Window128KN/A
Input Price$0.08/1M tokens$0.003/image/1M tokens
Output Price$0.14/1M tokensN/A/1M tokens
Latency~600ms~3s

Choose Llama 3.1 405B when:

  • ✓ Premium tasks
  • ✓ Research
  • ✓ Fine-tuning base
Key Strengths:

Largest open model, Highest open-source quality

Choose FLUX.1 Dev when:

  • ✓ Custom styles
  • ✓ Fine-tuned imagery
  • ✓ Development
Key Strengths:

Fine-tunable, Good quality, Open weights

Verdict: Llama 3.1 405B vs FLUX.1 Dev

For cost efficiency, FLUX.1 Dev wins at $0.003/image/1M input tokens. For speed, FLUX.1 Dev is faster at ~3s. Llama 3.1 405B excels at Premium tasks while FLUX.1 Dev is better for Custom styles. Both are available on XALEN through a single API — try them in the Playground to see which fits your workload.

Detailed Analysis

Pricing Comparison

Llama 3.1 405B costs $0.08/1M input tokens and $0.14/1M output tokens. FLUX.1 Dev costs $0.003/image input and N/A output. FLUX.1 Dev is 26.7x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.

Performance & Context

Llama 3.1 405B has a 128K context window with ~600ms latency. FLUX.1 Dev offers N/A context at ~3s. Llama 3.1 405B has the larger context window.

Best For

Llama 3.1 405B (Open Source) is optimized for: Premium tasks, Research, Fine-tuning base. FLUX.1 Dev (Image) works best for: Custom styles, Fine-tuned imagery, Development.

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 Llama 3.1 405B
response_a = client.chat.completions.create(
    model="llama-3-1-405b",
    messages=[{"role": "user", "content": "Your question here"}]
)

# Use FLUX.1 Dev
response_b = client.chat.completions.create(
    model="flux-1-dev",
    messages=[{"role": "user", "content": "Your question here"}]
)

Start Building with XALEN

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Get API Key Try in Playground

Frequently Asked Questions

Which is better, Llama 3.1 405B or FLUX.1 Dev?

Llama 3.1 405B (Open Source, 405B) offers Largest open model. FLUX.1 Dev (Image, 12B) offers Fine-tunable. Choose Llama 3.1 405B for Premium tasks or FLUX.1 Dev for Custom styles.

How much does Llama 3.1 405B cost vs FLUX.1 Dev?

Llama 3.1 405B: $0.08/1M input, $0.14/1M output. FLUX.1 Dev: $0.003/image/1M input, N/A/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 Llama 3.1 405B and FLUX.1 Dev 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.