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Claude Sonnet 4.6 vs Phi-3.5 Medium

A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.

Updated

Claude Sonnet 4.6 specs · Phi-3.5 Medium specs
Verdict by category
  • PriceTie

    Neither model publishes per-token API pricing.

  • Context windowClaude Sonnet 4.6

    Claude Sonnet 4.6 accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.

  • BenchmarksTie

    No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.

  • ModalitiesClaude Sonnet 4.6

    Claude Sonnet 4.6 supports 2 modalities (text, vision) vs 1 for Phi-3.5 Medium.

  • OpennessPhi-3.5 Medium

    Phi-3.5 Medium ships open weights (MIT); Claude Sonnet 4.6 is API-only.

On balance Claude Sonnet 4.6 edges ahead, winning 2 of 5 categories against Phi-3.5 Medium's 1. Neither model publishes per-token API pricing. Claude Sonnet 4.6 accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, Claude Sonnet 4.6 handles text, vision while Phi-3.5 Medium handles text, which can be the deciding factor before you even look at benchmarks. Phi-3.5 Medium ships open weights (MIT); Claude Sonnet 4.6 is API-only.

Claude Sonnet 4.6 is the newer of the two, released 17 months after Phi-3.5 Medium, which usually means a more recent knowledge cutoff and updated safety post-training. Claude Sonnet 4.6 is usually picked for coding llm and code review workloads, while Phi-3.5 Medium 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

SpecClaude Sonnet 4.6Phi-3.5 Medium
ProviderAnthropicMicrosoft
ReleasedJan 2026Aug 2024
Modalitiestext, visiontext
Context window200K tokens128K tokens
Max output,,
Input · 1MPricing not publishedPricing not published
Output · 1MPricing not publishedPricing not published
Knowledge cutoff,,
Open weightsNoYes (MIT)
API availableYesYes

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, vs ,
  • Heavy usage, 1M in / 500k out per day, vs ,
  • RAG workload, 5M in / 200k out per day, 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).

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • Claude Sonnet 4.6Pricing unavailable
  • Phi-3.5 MediumPricing unavailable

Benchmarks compared

Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.

Claude Sonnet 4.6Phi-3.5 Medium
  • MMLU,78.9
Pick Claude Sonnet 4.6 if

Claude Sonnet 4.6 fits when…

  • Excellent quality-cost ratio
  • Strong for code review and writing
  • Reliable tool-use
  • Long-context tasks, handles 200K tokens vs 128K for Phi-3.5 Medium.
  • Multimodal needs covering vision.
Pick Phi-3.5 Medium if

Phi-3.5 Medium fits when…

  • MIT license
  • 128k context
  • Strong reasoning at 14B
  • Self-hosting and on-prem requirements, open weights (MIT).
Don't want either?

Consider Claude Opus 4.7

Anthropic's mid-2026 flagship, ahead on SWE-bench, agent reliability, and writing quality.

See Claude Opus 4.7 specsClaude Sonnet 4.6 vs Claude Opus 4.7Phi-3.5 Medium vs Claude Opus 4.7

Frequently asked

  • Is Claude Sonnet 4.6 or Phi-3.5 Medium 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 Sonnet 4.6 accepts 200K tokens vs 128K for Phi-3.5 Medium.
  • Is Claude Sonnet 4.6 or Phi-3.5 Medium better for coding?
    Both Claude Sonnet 4.6 and Phi-3.5 Medium 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-3.5 Medium ships open weights (MIT). Claude Sonnet 4.6 is API-only.
  • When were Claude Sonnet 4.6 and Phi-3.5 Medium released?
    Claude Sonnet 4.6 was released by Anthropic on 2026-01-20. Phi-3.5 Medium was released by Microsoft on 2024-08-20.
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