Model comparison
Solar Pro 4 vs GPT-5.4 Pro
- Input
- $0.30
- Output
- $1.20
- Context
- 512K tokens
- Released
- 2026-08-06
- Input
- $30.00
- Output
- $180.00
- Context
- 1.05M
- Released
- 2026-03-05
GPT-5.4 Pro scores higher on 2 of the 2 benchmarks both models report; Solar Pro 4 is cheaper on input tokens ($0.3 vs $30 per 1M, 100×); GPT-5.4 Pro has the larger context window (1.05M vs 512K).
Specs and pricing side by side
| Spec | Solar Pro 4 | GPT-5.4 Pro |
|---|---|---|
| Maker | Upstage | OpenAI |
| Released | 2026-08-06 | 2026-03-05 |
| Context window | 512K tokens | 1.05M |
| Max output | 128K tokens | 128K |
| Input price | $0.30 | $30.00 |
| Output price | $1.20 | $180.00 |
| Parameters | Undisclosed | not published |
| License | Proprietary (Upstage API and on-premises) | Proprietary |
| Weights | API only | API onlysame |
| Modalities | Text | Text, Vision |
| Knowledge cutoff | February 2026 | August 31, 2025 |
Benchmarks both models report
| Benchmark | Solar Pro 4 | GPT-5.4 Pro |
|---|---|---|
| GPQA Diamond | 89% | 94.4% |
| BrowseComp | 49.2% | 89.3% |
Scores are as published by each maker or its cited source; harness, reasoning effort and date can differ between rows, so treat small gaps as ties. Sources are listed on each model page.
Which one should you pick?
Pick Solar Pro 4 if…
- Cost matters: input tokens cost 100× less ($0.3 vs $30 per 1M).
- Your use case is: reach for it when an agent has to work across several long documents, contracts or data files in one session.
Pick GPT-5.4 Pro if…
- You care about GPQA Diamond, BrowseComp (it scores higher on 2 shared benchmarks).
- You need the longer context (1.05M vs 512K).
- You need Vision input, which Solar Pro 4 lacks.
- Your use case is: long-horizon professional deliverables: financial models, slide decks, and legal analysis.
FAQ
Which is better, Solar Pro 4 or GPT-5.4 Pro?
GPT-5.4 Pro scores higher on 2 of the 2 benchmarks both models report; Solar Pro 4 is cheaper on input tokens ($0.3 vs $30 per 1M, 100×); GPT-5.4 Pro has the larger context window (1.05M vs 512K). The better pick depends on whether you value benchmark scores, price per token, context length or openness for your workload.
How much cheaper is Solar Pro 4?
Solar Pro 4: $0.30 input, $1.20 output. GPT-5.4 Pro: $30.00 input, $180.00 output (list API prices as published by each maker).
What are the context windows of Solar Pro 4 and GPT-5.4 Pro?
Solar Pro 4 offers 512K tokens with up to 128K tokens output; GPT-5.4 Pro offers 1.05M with up to 128K output.
Is Solar Pro 4 newer than GPT-5.4 Pro?
Solar Pro 4 was released 2026-08-06; GPT-5.4 Pro was released 2026-03-05.