Claude Opus 4 vs Claude Opus 4.5

Compare Claude Opus 4 and Claude Opus 4.5: 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 Claude Opus 4.5
CategoryFrontierFrontier
Parameters~2T~2.5T
Context Window200K200K
Input Price$0.15/1M tokens$0.15/1M tokens
Output Price$0.75/1M tokens$0.75/1M tokens
Latency~800ms~900ms

Choose Claude Opus 4 when:

  • ✓ Complex counseling
  • ✓ Detailed chart analysis
  • ✓ Enterprise reports
Key Strengths:

Deepest reasoning, Exceptional nuance, Best complex analysis

Choose Claude Opus 4.5 when:

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

Superior creativity, Nuanced reasoning, Complex analysis

Verdict: Claude Opus 4 vs Claude Opus 4.5

For cost efficiency, Claude Opus 4.5 wins at $0.15/1M input tokens. For speed, Claude Opus 4 is faster at ~800ms. Claude Opus 4 excels at Complex counseling while Claude Opus 4.5 is better for Creative writing. 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. Claude Opus 4.5 costs $0.15 input and $0.75 output. Both models are similarly priced. XALEN offers batch processing at 50% discount on both models.

Performance & Context

Claude Opus 4 has a 200K context window with ~800ms latency. Claude Opus 4.5 offers 200K context at ~900ms. Both have identical context windows.

Best For

Claude Opus 4 (Frontier) is optimized for: Complex counseling, Detailed chart analysis, Enterprise reports. Claude Opus 4.5 (Frontier) works best for: Creative writing, Complex analysis, Research.

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

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Get API Key Try in Playground

Frequently Asked Questions

Which is better, Claude Opus 4 or Claude Opus 4.5?

Claude Opus 4 (Frontier, ~2T) offers Deepest reasoning. Claude Opus 4.5 (Frontier, ~2.5T) offers Superior creativity. Choose Claude Opus 4 for Complex counseling or Claude Opus 4.5 for Creative writing.

How much does Claude Opus 4 cost vs Claude Opus 4.5?

Claude Opus 4: $0.15/1M input, $0.75/1M output. Claude Opus 4.5: $0.15/1M input, $0.75/1M 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 Claude Opus 4.5 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.