Comparing GPT-5.5 and GPT-5.4 mini
From GPT-3.5, which popularized ChatGPT, to GPT-4o, which introduced multimodality, OpenAI's GPT models have steadily improved in performance and efficiency. Today, the GPT-5 series has become the flagship.
The GPT-5 series automatically adjusts how deeply it reasons within a single model. It answers simple questions quickly and thinks longer before responding to complex ones.
In this lesson, we'll compare the two GPT-5 models used at CodeFriends: GPT-5.5 (high-performance) and GPT-5.4 mini (lightweight).
What is GPT-5.5?
GPT-5.5 is the high-performance model of the GPT-5 series, suited for tasks that require complex reasoning and refined output.
- Strengths: Complex reasoning, coding, data analysis, long-document processing
- Context: Handles up to about 1 million tokens at once
- Multimodal: Processes text and image (vision) inputs
- Trait: Reasons more deeply when needed, for higher accuracy
It fits quality-critical tasks like in-depth analysis or difficult coding problems.
What is GPT-5.4 mini?
GPT-5.4 mini is the lightweight model of the GPT-5 series, aiming to deliver near–GPT-5.5 quality faster and at a lower cost.
- Strengths: Fast response speed, low usage cost
- Best for: Everyday conversation, summarization, simple code, most real-time interactions
- Trait: Light and efficient, ideal for frequent calls
It is CodeFriends' default model, used for most practice sessions that need quick feedback.
Which model should you choose?
| Aspect | GPT-5.4 mini | GPT-5.5 |
|---|---|---|
| Character | Lightweight & fast | High-performance |
| Response speed | Fast | Moderate |
| Usage cost | Low | Relatively high |
| Recommended for | Everyday chat, summaries, simple code | Complex reasoning, coding, data analysis |
Choose GPT-5.4 mini when speed and efficiency matter, and GPT-5.5 when you need deeper reasoning and higher quality.
GPT also evolved through GPT-3.5, GPT-4, and GPT-4o, and includes various versions such as GPT-o1 and GPT-o3, which are strong at logical operations.
In the next lesson, we'll compare responses not only from OpenAI's GPT models but also with Claude from Anthropic and deepseek-chat from DeepSeek.
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