Inflection 3 Pi vs Claude 3.5 Sonnet (Thinking)

Compare Inflection 3 Pi and Claude 3.5 Sonnet (Thinking): 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 Inflection 3 Pi Claude 3.5 Sonnet (Thinking)
CategoryCompactReasoning
Parameters~40B~500B
Context Window128K200K
Input Price$0.02/1M tokens$0.03/1M tokens
Output Price$0.04/1M tokens$0.15/1M tokens
Latency~150ms~600ms

Choose Inflection 3 Pi when:

  • ✓ Personal assistants
  • ✓ Chat companions
  • ✓ Support bots
Key Strengths:

Conversational, Empathetic, Fast

Choose Claude 3.5 Sonnet (Thinking) when:

  • ✓ Complex analysis
  • ✓ Multi-step logic
  • ✓ Verification tasks
Key Strengths:

Transparent thinking, Strong reasoning, Self-correction

Verdict: Inflection 3 Pi vs Claude 3.5 Sonnet (Thinking)

For cost efficiency, Inflection 3 Pi wins at $0.02/1M input tokens. For speed, Inflection 3 Pi is faster at ~150ms. Inflection 3 Pi excels at Personal assistants while Claude 3.5 Sonnet (Thinking) is better for Complex analysis. Both are available on XALEN through a single API — try them in the Playground to see which fits your workload.

Detailed Analysis

Pricing Comparison

Inflection 3 Pi costs $0.02/1M input tokens and $0.04/1M output tokens. Claude 3.5 Sonnet (Thinking) costs $0.03 input and $0.15 output. Inflection 3 Pi is 1.5x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.

Performance & Context

Inflection 3 Pi has a 128K context window with ~150ms latency. Claude 3.5 Sonnet (Thinking) offers 200K context at ~600ms. Claude 3.5 Sonnet (Thinking) has the larger context window.

Best For

Inflection 3 Pi (Compact) is optimized for: Personal assistants, Chat companions, Support bots. Claude 3.5 Sonnet (Thinking) (Reasoning) works best for: Complex analysis, Multi-step logic, Verification tasks.

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 Inflection 3 Pi
response_a = client.chat.completions.create(
    model="inflection-3-pi",
    messages=[{"role": "user", "content": "Your question here"}]
)

# Use Claude 3.5 Sonnet (Thinking)
response_b = client.chat.completions.create(
    model="claude-3-5-sonnet-thinking",
    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, Inflection 3 Pi or Claude 3.5 Sonnet (Thinking)?

Inflection 3 Pi (Compact, ~40B) offers Conversational. Claude 3.5 Sonnet (Thinking) (Reasoning, ~500B) offers Transparent thinking. Choose Inflection 3 Pi for Personal assistants or Claude 3.5 Sonnet (Thinking) for Complex analysis.

How much does Inflection 3 Pi cost vs Claude 3.5 Sonnet (Thinking)?

Inflection 3 Pi: $0.02/1M input, $0.04/1M output. Claude 3.5 Sonnet (Thinking): $0.03/1M input, $0.15/1M 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 Inflection 3 Pi and Claude 3.5 Sonnet (Thinking) 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.