LLM·Dex
Newsletter

Phi-4 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-4 specs · Yi-Lightning specs
Verdict by category
  • PriceYi-Lightning

    Yi-Lightning publishes pricing ($0.14 / 1M output tokens) while Phi-4 does not.

  • Context windowTie

    Both ship a 16K-token context window.

  • BenchmarksTie

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

  • ModalitiesTie

    Both handle text.

  • OpennessPhi-4

    Phi-4 ships open weights (MIT); Yi-Lightning is API-only.

It's a genuine coin-flip between Phi-4 and Yi-Lightning: 1 category wins each, with the rest tied. Yi-Lightning publishes pricing ($0.14 / 1M output tokens) while Phi-4 does not. Both ship a 16K-token context window.

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-4 ships open weights (MIT); Yi-Lightning is API-only.

Phi-4 is the newer of the two, released 2 months after Yi-Lightning, which usually means a more recent knowledge cutoff and updated safety post-training. Phi-4 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-4Yi-Lightning
ProviderMicrosoftOther
ReleasedDec 2024Oct 2024
Modalitiestexttext
Context window16K 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-4Pricing 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-4Yi-Lightning
  • MMLU84.8
  • HumanEval82.6
Pick Phi-4 if

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).
Pick Yi-Lightning if

Yi-Lightning fits when…

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

Consider Phi-3.5 Medium

14B Phi-3.5, predecessor to Phi-4 with strong benchmark efficiency for its size.

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

Frequently asked

  • Is Phi-4 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?
    Both Phi-4 and Yi-Lightning ship a 16K-token context window.
  • Is Phi-4 or Yi-Lightning better for coding?
    Both Phi-4 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-4 ships open weights (MIT). Yi-Lightning is API-only.
  • When were Phi-4 and Yi-Lightning released?
    Phi-4 was released by Microsoft on 2024-12-12. Yi-Lightning was released by Other on 2024-10-16.
Friday digest

The week's AI launches, in your inbox.

One short email every Friday, new models, leaks, and quietly-shipped APIs you missed.