GPT-5.4 nano is the most lightweight and cost-efficient variant of the GPT-5.4 family, optimized for speed-critical and high-volume tasks. It supports text and image inputs and is designed for low-latency...
Model details →OpenAI: GPT-5.4 Nano vs Upstage: Solar Pro 4
Upstage: Solar Pro 4 wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
Solar Pro 4 is Upstage's cost-efficient large language model, featuring a 524K context window. It is built for long-horizon tasks and agentic workflows, with strong capabilities in office productivity, document-intensive...
Model details →Side-by-side comparison
| Capability | OpenAI: GPT-5.4 Nano | Upstage: Solar Pro 4 | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 400K | 524K | 🏆 Upstage: Solar Pro 4 |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $0.20 | $0.09 | 🏆 Upstage: Solar Pro 4 |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $1.25 | $0.36 | 🏆 Upstage: Solar Pro 4 |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | — | 🏆 OpenAI: GPT-5.4 Nano |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is OpenAI: GPT-5.4 Nano better than Upstage: Solar Pro 4?
Upstage: Solar Pro 4 wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between OpenAI: GPT-5.4 Nano and Upstage: Solar Pro 4?
Input: $0.20 vs $0.09 per 1M tokens. Output: $1.25 vs $0.36 per 1M tokens.
What context windows do OpenAI: GPT-5.4 Nano and Upstage: Solar Pro 4 support?
OpenAI: GPT-5.4 Nano supports up to 400K tokens. Upstage: Solar Pro 4 supports up to 524K tokens.
Do both OpenAI: GPT-5.4 Nano and Upstage: Solar Pro 4 support tool calling?
OpenAI: GPT-5.4 Nano: yes. Upstage: Solar Pro 4: yes.