Claude Opus 4 vs Mistral Small 3.1

Compare Claude Opus 4 and Mistral Small 3.1: 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 Mistral Small 3.1
CategoryFrontierCompact
Parameters~2T24B
Context Window200K128K
Input Price$0.15/1M tokens$0.02/1M tokens
Output Price$0.75/1M tokens$0.04/1M tokens
Latency~800ms~120ms

Choose Claude Opus 4 when:

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

Deepest reasoning, Exceptional nuance, Best complex analysis

Choose Mistral Small 3.1 when:

  • ✓ Lightweight tasks
  • ✓ Classification
  • ✓ Simple generation
Key Strengths:

128K context, Low cost, Fast

Verdict: Claude Opus 4 vs Mistral Small 3.1

For cost efficiency, Mistral Small 3.1 wins at $0.02/1M input tokens. For speed, Mistral Small 3.1 is faster at ~120ms. Claude Opus 4 excels at Complex counseling while Mistral Small 3.1 is better for Lightweight 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. Mistral Small 3.1 costs $0.02 input and $0.04 output. Mistral Small 3.1 is 7.5x 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. Mistral Small 3.1 offers 128K context at ~120ms. Claude Opus 4 has the larger context window.

Best For

Claude Opus 4 (Frontier) is optimized for: Complex counseling, Detailed chart analysis, Enterprise reports. Mistral Small 3.1 (Compact) works best for: Lightweight tasks, Classification, Simple generation.

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 Mistral Small 3.1
response_b = client.chat.completions.create(
    model="mistral-small-3-1",
    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 Mistral Small 3.1?

Claude Opus 4 (Frontier, ~2T) offers Deepest reasoning. Mistral Small 3.1 (Compact, 24B) offers 128K context. Choose Claude Opus 4 for Complex counseling or Mistral Small 3.1 for Lightweight tasks.

How much does Claude Opus 4 cost vs Mistral Small 3.1?

Claude Opus 4: $0.15/1M input, $0.75/1M output. Mistral Small 3.1: $0.02/1M input, $0.04/1M 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 Mistral Small 3.1 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.