ModelRefs / Phi-4 vs Claude Sonnet 4.5
Phi-4 vs Claude Sonnet 4.5
Phi-4 vs Claude Sonnet 4.5: side-by-side benchmarks, pricing, context windows, coding ability and deployment. Pick the right model for your stack.
Overview
Claude Sonnet 4.5: Claude Sonnet 4.5 is Anthropic's balanced frontier model, designed for complex reasoning, coding, and agentic tasks while maintaining production-grade speed. It builds on the Claude 4 family's emphasis on honesty and reduced hallucination rates.
Phi-4: Microsoft's 14B dense decoder-only open-weight text model, trained on 9.8T tokens with a synthetic-data-centered curriculum and available through the microsoft/phi-4 artifact and Microsoft Foundry.
Context window: Claude Sonnet 4.5 accepts up to 200,000 tokens, Phi-4 up to 16,384. Confirm the limit for your specific deployment channel before relying on it.
Claude Sonnet 4.5 vs Phi-4 at a glance
| Attribute | Claude Sonnet 4.5 | Phi-4 |
|---|---|---|
| Provider | Anthropic | Microsoft |
| Released | 2025-09-29 | 2024-12-12 |
| Context window | 200,000 tokens | 16,384 tokens |
| Input price | $3/M tokens | Free / self-hosted |
| Output price | $15/M tokens | Free / self-hosted |
| Licence | Proprietary | MIT |
| Self-hostable | No, hosted only | Yes, open weights |
| Modalities | text, vision | text |
Where they differ most
- Cost Efficiency: Claude Sonnet 4.5 37%, Phi-4 100%. Phi-4 leads on this dimension.
- Coding: Claude Sonnet 4.5 77%, Phi-4 67%. Claude Sonnet 4.5 leads on this dimension.
Capability scores are ModelRefs' own derived signals, not vendor claims or benchmark results. Validate against your own workload before relying on them.
Continue your research
Use these connected ModelRefs sections to compare alternatives, inspect implementation paths, and review the evidence and governance boundaries relevant to Phi-4 vs Claude Sonnet 4.5.
Frequently asked questions
Which is better, Phi-4 or Claude Sonnet 4.5?
Phi-4 and Claude Sonnet 4.5 target different workloads — see the benchmark and pricing tables for a side-by-side answer.
Is Phi-4 cheaper than Claude Sonnet 4.5?
Compare $0.00000 vs $0.00300 on this page.