OpenAI · Microsoft
GPT-5.5 Thinking vs Phi-4-reasoning-plus
Compare GPT-5.5 Thinking (OpenAI) and Phi-4-reasoning-plus (Microsoft) on benchmarks, capabilities, and pricing.
At a glance
| GPT-5.5 Thinking | Phi-4-reasoning-plus | |
|---|---|---|
| Provider | OpenAI | Microsoft |
| Context | 1M tokens | 32K tokens |
| Modality | Multimodal | Text only |
| Pricing | Max | Pro |
| Speed | Slow | Medium |
| Reasoning | Expert | Expert |
Benchmarks
GPT-5.5 Thinking
- AA Intelligence Index
- 56pointsEstimated · As of Aug 11, 2026Stale · 31d old
- Output speed
- 52tokens/sEstimated · As of Aug 11, 2026Stale · 31d old
- API input cost
- Not available
- API output cost
- Not available
- Context window
- 1MEstimated · As of Aug 11, 2026Stale · 31d old
AA measurements unavailable
Phi-4-reasoning-plus
- AA Intelligence Index
- Not available
- Output speed
- Not available
- API input cost
- Not available
- API output cost
- Not available
- Context window
- 32KCatalog · As of Aug 24, 2026Within 30d
AA measurements unavailable
When to pick GPT-5.5 Thinking
Choose GPT-5.5 Thinking when problems demand extended deliberation depth: multi-step legal analysis, complex SQL generation across unfamiliar schemas, math-heavy research questions, or competitive-programming-style coding tasks. Suits teams willing to pay higher per-token cost and accept longer latency in exchange for thorough chain-of-thought across long, ambiguous prompts that benefit from extra reasoning budget.
When to pick Phi-4-reasoning-plus
Choose Phi-4 Reasoning Plus when you want chain-of-thought capability in a compact footprint. Fits structured math tutoring at scale, on-device step-by-step troubleshooting assistants, batch evaluation of student answers, and self-hosted reasoning behind firewalls. Suits teams that need reasoning traces without committing to a frontier-tier model's cost or latency profile.
Switch between GPT-5.5 Thinking and Phi-4-reasoning-plus per task with one account.
Frequently asked
- Which is faster, GPT-5.5 Thinking or Phi-4-reasoning-plus?
- GPT-5.5 Thinking is rated slow and Phi-4-reasoning-plus is rated medium. yno.ai surfaces output-speed scores from Artificial Analysis on each model's detail page so you can compare exact tokens-per-second figures for your workload.
- Which is cheaper, GPT-5.5 Thinking or Phi-4-reasoning-plus?
- GPT-5.5 Thinking is on the max tier in yno.ai; Phi-4-reasoning-plus is on the pro tier. See the pricing page for the latest per-tier limits.
- Which is better for Math proofs?
- Both models support Math proofs. GPT-5.5 Thinking brings Reasoning summaries; Phi-4-reasoning-plus brings Reinforcement-learning tuning. Run a side-by-side eval on your prompts in yno.ai to see which fits your workload.
- Can I use both GPT-5.5 Thinking and Phi-4-reasoning-plus in yno.ai?
- Yes. Both are available on yno.ai under your single account; you can route different stages of an agent to different models or A/B test them on the same prompt without per-provider boilerplate.