Claude Opus 4.5 vs SD 3.5 Medium

Compare Claude Opus 4.5 and SD 3.5 Medium: 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 Opus 4.5 SD 3.5 Medium
CategoryFrontierImage
Parameters~2.5T2.5B
Context Window200KN/A
Input Price$0.15/1M tokens$0.003/image/1M tokens
Output Price$0.75/1M tokensN/A/1M tokens
Latency~900ms~2s

Choose Claude Opus 4.5 when:

  • ✓ Creative writing
  • ✓ Complex analysis
  • ✓ Research
Key Strengths:

Superior creativity, Nuanced reasoning, Complex analysis

Choose SD 3.5 Medium when:

  • ✓ General imagery
  • ✓ Batch generation
  • ✓ Prototyping
Key Strengths:

Good quality, Fast, Open weights

Verdict: Claude Opus 4.5 vs SD 3.5 Medium

For cost efficiency, SD 3.5 Medium wins at $0.003/image/1M input tokens. For speed, SD 3.5 Medium is faster at ~2s. Claude Opus 4.5 excels at Creative writing while SD 3.5 Medium is better for General imagery. 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 4.5 costs $0.15/1M input tokens and $0.75/1M output tokens. SD 3.5 Medium costs $0.003/image input and N/A output. SD 3.5 Medium is 50.0x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.

Performance & Context

Claude Opus 4.5 has a 200K context window with ~900ms latency. SD 3.5 Medium offers N/A context at ~2s. Claude Opus 4.5 has the larger context window.

Best For

Claude Opus 4.5 (Frontier) is optimized for: Creative writing, Complex analysis, Research. SD 3.5 Medium (Image) works best for: General imagery, Batch generation, Prototyping.

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

# Use SD 3.5 Medium
response_b = client.chat.completions.create(
    model="stable-diffusion-3-5-medium",
    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, Claude Opus 4.5 or SD 3.5 Medium?

Claude Opus 4.5 (Frontier, ~2.5T) offers Superior creativity. SD 3.5 Medium (Image, 2.5B) offers Good quality. Choose Claude Opus 4.5 for Creative writing or SD 3.5 Medium for General imagery.

How much does Claude Opus 4.5 cost vs SD 3.5 Medium?

Claude Opus 4.5: $0.15/1M input, $0.75/1M output. SD 3.5 Medium: $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 Claude Opus 4.5 and SD 3.5 Medium 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.