GPT-5.4 Pro is OpenAI's most advanced model, building on GPT-5.4's unified architecture with enhanced reasoning capabilities for complex, high-stakes tasks. It features a 1M+ token context window (922K input, 128K...
Model details →OpenAI: GPT-5.4 Pro vs OpenAI: GPT-5.5 Pro
OpenAI: GPT-5.4 Pro and OpenAI: GPT-5.5 Pro are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...
Model details →Side-by-side comparison
| Capability | OpenAI: GPT-5.4 Pro | OpenAI: GPT-5.5 Pro | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 1.1M | 1.1M | Tie |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $30.00 | $30.00 | Tie |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $180.00 | $180.00 | Tie |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is OpenAI: GPT-5.4 Pro better than OpenAI: GPT-5.5 Pro?
OpenAI: GPT-5.4 Pro and OpenAI: GPT-5.5 Pro are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
What's the price difference between OpenAI: GPT-5.4 Pro and OpenAI: GPT-5.5 Pro?
Input: $30.00 vs $30.00 per 1M tokens. Output: $180.00 vs $180.00 per 1M tokens.
What context windows do OpenAI: GPT-5.4 Pro and OpenAI: GPT-5.5 Pro support?
OpenAI: GPT-5.4 Pro supports up to 1.1M tokens. OpenAI: GPT-5.5 Pro supports up to 1.1M tokens.
Do both OpenAI: GPT-5.4 Pro and OpenAI: GPT-5.5 Pro support tool calling?
OpenAI: GPT-5.4 Pro: yes. OpenAI: GPT-5.5 Pro: yes.
Compare OpenAI: GPT-5.4 Pro with other models
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