Claude 3.5 Sonnet vs Phi-4
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
Claude 3.5 Sonnet specs · Phi-4 specs- PriceClaude 3.5 Sonnet
Claude 3.5 Sonnet publishes pricing ($15.00 / 1M output tokens) while Phi-4 does not.
- Context windowClaude 3.5 Sonnet
Claude 3.5 Sonnet accepts 200K tokens vs 16K, 12.5× the room for long documents and codebases.
- BenchmarksClaude 3.5 Sonnet
Claude 3.5 Sonnet leads in 1 of 1 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 92.0 vs 82.6.
- ModalitiesClaude 3.5 Sonnet
Claude 3.5 Sonnet supports 2 modalities (text, vision) vs 1 for Phi-4.
- OpennessPhi-4
Phi-4 ships open weights (MIT); Claude 3.5 Sonnet is API-only.
On balance Claude 3.5 Sonnet edges ahead, winning 4 of 5 categories against Phi-4's 1. Claude 3.5 Sonnet publishes pricing ($15.00 / 1M output tokens) while Phi-4 does not. Claude 3.5 Sonnet accepts 200K tokens vs 16K, 12.5× the room for long documents and codebases.
Claude 3.5 Sonnet leads in 1 of 1 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 92.0 vs 82.6. They differ in modality coverage, Claude 3.5 Sonnet handles text, vision while Phi-4 handles text, which can be the deciding factor before you even look at benchmarks. Phi-4 ships open weights (MIT); Claude 3.5 Sonnet is API-only.
Phi-4 is the newer of the two, released 2 months after Claude 3.5 Sonnet, which usually means a more recent knowledge cutoff and updated safety post-training. Claude 3.5 Sonnet is usually picked for coding llm and code review workloads, while Phi-4 sees more deployments in on device and edge deployment. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | Claude 3.5 Sonnet | Phi-4 |
|---|---|---|
| Provider | Anthropic | Microsoft |
| Released | Oct 2024 | Dec 2024 |
| Modalities | text, vision | text |
| Context window | 200K tokens | 16K tokens |
| Max output | , | , |
| Input · 1M | $3.00 / 1M tokens | Pricing not published |
| Output · 1M | $15.00 / 1M tokens | Pricing not published |
| Knowledge cutoff | , | , |
| Open weights | No | Yes (MIT) |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day$31.50 vs ,
- Heavy usage, 1M in / 500k out per day$315 vs ,
- RAG workload, 5M in / 200k out per day$540 vs ,
Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- Claude 3.5 Sonnet$1.05
- Phi-4Pricing unavailable
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
- MMLU,84.8
- HumanEval92.082.6
Claude 3.5 Sonnet fits when…
- Mature and battle-tested
- Strong code
- Long-context tasks, handles 200K tokens vs 16K for Phi-4.
- Multimodal needs covering vision.
Phi-4 fits when…
- Exceptional quality at 14B parameters
- MIT license, clean commercial use
- Strong on math
- Self-hosting and on-prem requirements, open weights (MIT).
Consider Claude Opus 4.7
Anthropic's mid-2026 flagship, ahead on SWE-bench, agent reliability, and writing quality.
Frequently asked
Is Claude 3.5 Sonnet or Phi-4 cheaper?
Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.Which has the larger context window?
Claude 3.5 Sonnet accepts 200K tokens vs 16K for Phi-4.Is Claude 3.5 Sonnet or Phi-4 better for coding?
Both Claude 3.5 Sonnet and Phi-4 are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Phi-4 ships open weights (MIT). Claude 3.5 Sonnet is API-only.When were Claude 3.5 Sonnet and Phi-4 released?
Claude 3.5 Sonnet was released by Anthropic on 2024-10-22. Phi-4 was released by Microsoft on 2024-12-12.
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