GPT-5 nano 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 nano specs · Phi-4 specs- PriceGPT-5 nano
GPT-5 nano publishes pricing ($0.40 / 1M output tokens) while Phi-4 does not.
- Context windowGPT-5 nano
GPT-5 nano accepts 400K tokens vs 16K, 25.0× 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.
- ModalitiesGPT-5 nano
GPT-5 nano supports 2 modalities (text, vision) vs 1 for Phi-4.
- OpennessPhi-4
Phi-4 ships open weights (MIT); GPT-5 nano is API-only.
On balance GPT-5 nano edges ahead, winning 3 of 5 categories against Phi-4's 1. GPT-5 nano publishes pricing ($0.40 / 1M output tokens) while Phi-4 does not. GPT-5 nano accepts 400K tokens vs 16K, 25.0× the room for long documents and codebases.
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, GPT-5 nano 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); GPT-5 nano is API-only.
GPT-5 nano 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 nano is usually picked for cheapest llm and fastest llm 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 | GPT-5 nano | Phi-4 |
|---|---|---|
| Provider | OpenAI | Microsoft |
| Released | Aug 2025 | Dec 2024 |
| Modalities | text, vision | text |
| Context window | 400K tokens | 16K tokens |
| Max output | 128K tokens | , |
| Input · 1M | $0.050 / 1M tokens | Pricing not published |
| Output · 1M | $0.40 / 1M tokens | Pricing not published |
| Knowledge cutoff | 2024-09 | , |
| 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$0.750 vs ,
- Heavy usage, 1M in / 500k out per day$7.50 vs ,
- RAG workload, 5M in / 200k out per day$9.90 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.
- GPT-5 nano$0.025
- 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
- HumanEval,82.6
GPT-5 nano fits when…
- Lowest-cost OpenAI model with vision support
- Fast P99 latency
- Good enough for routing and classification
- Long-context tasks, handles 400K 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 GPT-5.5
OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.
Frequently asked
Is GPT-5 nano 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 nano accepts 400K tokens vs 16K for Phi-4.Is GPT-5 nano or Phi-4 better for coding?
Both GPT-5 nano 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 nano is API-only.When were GPT-5 nano and Phi-4 released?
GPT-5 nano was released by OpenAI on 2025-08-07. Phi-4 was released by Microsoft on 2024-12-12.
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