GPT-5.5 vs OpenAI: o4 Mini Deep Research

Side-by-side comparison. Updated 2026-06-07.

Verdict

GPT-5.5 wins on higher overall score (9.4 vs 8.4, +1.0).

Both models score equally. Pick based on which strengths align with your workload.

GPT-5.5
by OpenAI
9.4 /10 Elite
Full review →
OpenAI: o4 Mini Deep Research
by OpenAI
8.4 /10 Excellent
Full review →

At a Glance

Side-by-side comparison of GPT-5.5 and OpenAI: o4 Mini Deep Research
Attribute GPT-5.5 OpenAI: o4 Mini Deep Research
Provider OpenAI OpenAI
Tags general Reasoning Fast
Context 128,000 tokens 200,000 tokens
Input price $12.50/1M $2.00/1M
Output price $8.00/1M $8.00/1M
Input modalities Text File, Image, Text
Output modalities Text Text

GPT-5.5 Strengths

  • Strong general knowledge
  • Deep reasoning chain-of-thought
  • Reliable structured output
  • Broad tool-use capability
  • Excellent multilingual support

OpenAI: o4 Mini Deep Research Strengths

  • Cost-effective deep research capability
  • Faster than o3 Deep Research
  • Strong structured output quality
  • Good multi-step reasoning