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Phi-3.5 Medium vs Yi-Lightning

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

Updated

Phi-3.5 Medium specs · Yi-Lightning specs
Verdict by category
  • PriceYi-Lightning

    Yi-Lightning publishes pricing ($0.14 / 1M output tokens) while Phi-3.5 Medium does not.

  • Context windowPhi-3.5 Medium

    Phi-3.5 Medium accepts 128K tokens vs 16K, 8.0× 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.

  • ModalitiesTie

    Both handle text.

  • OpennessPhi-3.5 Medium

    Phi-3.5 Medium ships open weights (MIT); Yi-Lightning is API-only.

On balance Phi-3.5 Medium edges ahead, winning 2 of 5 categories against Yi-Lightning's 1. Yi-Lightning publishes pricing ($0.14 / 1M output tokens) while Phi-3.5 Medium does not. Phi-3.5 Medium accepts 128K tokens vs 16K, 8.0× the room for long documents and codebases.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. Both target the same set of modalities (text), so the deciding factors are price, context, and raw quality. Phi-3.5 Medium ships open weights (MIT); Yi-Lightning is API-only.

Yi-Lightning is the newer of the two, released 2 months after Phi-3.5 Medium, which usually means a more recent knowledge cutoff and updated safety post-training. Phi-3.5 Medium is usually picked for on device and edge deployment workloads, while Yi-Lightning sees more deployments in chinese llm and cheapest llm. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecPhi-3.5 MediumYi-Lightning
ProviderMicrosoftOther
ReleasedAug 2024Oct 2024
Modalitiestexttext
Context window128K tokens16K tokens
Max output,,
Input · 1MPricing not published$0.14 / 1M tokens
Output · 1MPricing not published$0.14 / 1M tokens
Knowledge cutoff,,
Open weightsYes (MIT)No
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 $0.630
  • Heavy usage, 1M in / 500k out per day, vs $6.30
  • RAG workload, 5M in / 200k out per day, vs $21.84

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.

  • Phi-3.5 MediumPricing unavailable
  • Yi-Lightning$0.021

Benchmarks compared

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

Phi-3.5 MediumYi-Lightning
  • MMLU78.9
Pick Phi-3.5 Medium if

Phi-3.5 Medium fits when…

  • MIT license
  • 128k context
  • Strong reasoning at 14B
  • Long-context tasks, handles 128K tokens vs 16K for Yi-Lightning.
  • Self-hosting and on-prem requirements, open weights (MIT).
Pick Yi-Lightning if

Yi-Lightning fits when…

  • Cheap
  • Strong Chinese
  • Fast
Don't want either?

Consider Phi-4

Microsoft's 14B model, exceptional quality-per-parameter via curated synthetic training data.

See Phi-4 specsPhi-3.5 Medium vs Phi-4Yi-Lightning vs Phi-4

Frequently asked

  • Is Phi-3.5 Medium or Yi-Lightning 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?
    Phi-3.5 Medium accepts 128K tokens vs 16K for Yi-Lightning.
  • Is Phi-3.5 Medium or Yi-Lightning better for coding?
    Both Phi-3.5 Medium and Yi-Lightning 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). Yi-Lightning is API-only.
  • When were Phi-3.5 Medium and Yi-Lightning released?
    Phi-3.5 Medium was released by Microsoft on 2024-08-20. Yi-Lightning was released by Other on 2024-10-16.
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