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GPT-5 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

GPT-5 specs · Phi-4 specs
Verdict by category
  • PriceGPT-5

    GPT-5 publishes pricing ($10.00 / 1M output tokens) while Phi-4 does not.

  • Context windowGPT-5

    GPT-5 accepts 400K tokens vs 16K, 25.0× the room for long documents and codebases.

  • BenchmarksGPT-5

    GPT-5 leads in 2 of 2 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 96.2 vs 82.6.

  • ModalitiesGPT-5

    GPT-5 supports 3 modalities (text, vision, audio) vs 1 for Phi-4.

  • OpennessPhi-4

    Phi-4 ships open weights (MIT); GPT-5 is API-only.

On balance GPT-5 edges ahead, winning 4 of 5 categories against Phi-4's 1. GPT-5 publishes pricing ($10.00 / 1M output tokens) while Phi-4 does not. GPT-5 accepts 400K tokens vs 16K, 25.0× the room for long documents and codebases.

GPT-5 leads in 2 of 2 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 96.2 vs 82.6. They differ in modality coverage, GPT-5 handles text, vision, audio while Phi-4 handles text, which can be the deciding factor before you even look at benchmarks. Phi-4 ships open weights (MIT); GPT-5 is API-only.

GPT-5 is the newer of the two, released 8 months after Phi-4, which usually means a more recent knowledge cutoff and updated safety post-training. GPT-5 is usually picked for coding llm and agents 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

SpecGPT-5Phi-4
ProviderOpenAIMicrosoft
ReleasedAug 2025Dec 2024
Modalitiestext, vision, audiotext
Context window400K tokens16K tokens
Max output128K tokens,
Input · 1M$1.25 / 1M tokensPricing not published
Output · 1M$10.00 / 1M tokensPricing not published
Knowledge cutoff2024-09,
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$18.75 vs ,
  • Heavy usage, 1M in / 500k out per day$188 vs ,
  • RAG workload, 5M in / 200k out per day$248 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.

  • GPT-5$0.625
  • 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.

GPT-5Phi-4
  • MMLU91.484.8
  • HumanEval96.282.6
  • GPQA89.4
  • SWE-bench Verified74.9
Pick GPT-5 if

GPT-5 fits when…

  • Unified model, reasoning routed automatically per query
  • Excellent tool-use and JSON-mode discipline
  • Strong agent performance on SWE-bench Verified
  • Long-context tasks, handles 400K tokens vs 16K for Phi-4.
  • Multimodal needs covering vision, audio.
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).
Don't want either?

Consider GPT-5.5

OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.

See GPT-5.5 specsGPT-5 vs GPT-5.5Phi-4 vs GPT-5.5

Frequently asked

  • Is GPT-5 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?
    GPT-5 accepts 400K tokens vs 16K for Phi-4.
  • Is GPT-5 or Phi-4 better for coding?
    Both GPT-5 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). GPT-5 is API-only.
  • When were GPT-5 and Phi-4 released?
    GPT-5 was released by OpenAI on 2025-08-07. Phi-4 was released by Microsoft on 2024-12-12.
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