Claude Sonnet 4.5 vs FLUX 1.1 Pro

Compare Claude Sonnet 4.5 and FLUX 1.1 Pro: 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 Claude Sonnet 4.5 FLUX 1.1 Pro
CategoryFrontierImage
Parameters~600B24B
Context Window200KN/A
Input Price$0.03/1M tokens$0.05/image/1M tokens
Output Price$0.15/1M tokensN/A/1M tokens
Latency~350ms~4s

Choose Claude Sonnet 4.5 when:

  • ✓ Code generation
  • ✓ Structured output
  • ✓ Automation
Key Strengths:

Strong coding, Better instruction following, Reliable

Choose FLUX 1.1 Pro when:

  • ✓ Premium marketing
  • ✓ Temple artwork
  • ✓ Product photography
Key Strengths:

Highest quality, Best prompt adherence, Professional grade

Verdict: Claude Sonnet 4.5 vs FLUX 1.1 Pro

For cost efficiency, Claude Sonnet 4.5 wins at $0.03/1M input tokens. For speed, Claude Sonnet 4.5 is faster at ~350ms. Claude Sonnet 4.5 excels at Code generation while FLUX 1.1 Pro is better for Premium marketing. 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 Sonnet 4.5 costs $0.03/1M input tokens and $0.15/1M output tokens. FLUX 1.1 Pro costs $0.05/image input and N/A output. Claude Sonnet 4.5 is 1.7x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.

Performance & Context

Claude Sonnet 4.5 has a 200K context window with ~350ms latency. FLUX 1.1 Pro offers N/A context at ~4s. Claude Sonnet 4.5 has the larger context window.

Best For

Claude Sonnet 4.5 (Frontier) is optimized for: Code generation, Structured output, Automation. FLUX 1.1 Pro (Image) works best for: Premium marketing, Temple artwork, Product photography.

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 Sonnet 4.5
response_a = client.chat.completions.create(
    model="claude-sonnet-4-5",
    messages=[{"role": "user", "content": "Your question here"}]
)

# Use FLUX 1.1 Pro
response_b = client.chat.completions.create(
    model="flux-1-1-pro",
    messages=[{"role": "user", "content": "Your question here"}]
)

Start Building with XALEN

200+ AI models. One API. Pay-as-you-go.

Get API Key Try in Playground

Frequently Asked Questions

Which is better, Claude Sonnet 4.5 or FLUX 1.1 Pro?

Claude Sonnet 4.5 (Frontier, ~600B) offers Strong coding. FLUX 1.1 Pro (Image, 24B) offers Highest quality. Choose Claude Sonnet 4.5 for Code generation or FLUX 1.1 Pro for Premium marketing.

How much does Claude Sonnet 4.5 cost vs FLUX 1.1 Pro?

Claude Sonnet 4.5: $0.03/1M input, $0.15/1M output. FLUX 1.1 Pro: $0.05/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 Claude Sonnet 4.5 and FLUX 1.1 Pro 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.