Claude Sonnet 4.5 vs Phi-4
Compare Claude Sonnet 4.5 and Phi-4: pricing, performance, context window, latency, and best use cases. Side-by-side comparison on XALEN.
Updated 2026-05-21 · By Abhishek Raj · Our methodology
| Feature | Claude Sonnet 4.5 | Phi-4 |
|---|---|---|
| Category | Frontier | Compact |
| Parameters | ~600B | 14B |
| Context Window | 200K | 16K |
| Input Price | $0.03/1M tokens | $0.01/1M tokens |
| Output Price | $0.15/1M tokens | $0.02/1M tokens |
| Latency | ~350ms | ~100ms |
Choose Claude Sonnet 4.5 when:
- ✓ Code generation
- ✓ Structured output
- ✓ Automation
Strong coding, Better instruction following, Reliable
Choose Phi-4 when:
- ✓ Edge deployments
- ✓ Cost-sensitive apps
- ✓ Classification
Very compact, Strong reasoning for size, Extremely low cost
Verdict: Claude Sonnet 4.5 vs Phi-4
For cost efficiency, Phi-4 wins at $0.01/1M input tokens. For speed, Phi-4 is faster at ~100ms. Claude Sonnet 4.5 excels at Code generation while Phi-4 is better for Edge deployments. 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. Phi-4 costs $0.01 input and $0.02 output. Phi-4 is 3.0x 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. Phi-4 offers 16K context at ~100ms. Claude Sonnet 4.5 has the larger context window.
Best For
Claude Sonnet 4.5 (Frontier) is optimized for: Code generation, Structured output, Automation. Phi-4 (Compact) works best for: Edge deployments, Cost-sensitive apps, Classification.
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 Phi-4
response_b = client.chat.completions.create(
model="phi-4",
messages=[{"role": "user", "content": "Your question here"}]
)Frequently Asked Questions
Which is better, Claude Sonnet 4.5 or Phi-4?
Claude Sonnet 4.5 (Frontier, ~600B) offers Strong coding. Phi-4 (Compact, 14B) offers Very compact. Choose Claude Sonnet 4.5 for Code generation or Phi-4 for Edge deployments.
How much does Claude Sonnet 4.5 cost vs Phi-4?
Claude Sonnet 4.5: $0.03/1M input, $0.15/1M output. Phi-4: $0.01/1M input, $0.02/1M 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 Phi-4 by changing the model parameter. No code changes needed.
Related Comparisons
Last updated: 2026-05-21. Pricing and specifications may change. Check pricing page for latest rates.