GPT-5.5 Pro vs OpenAI o4-mini
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
OpenAI · Apr 2026
The maximum-compute tier of GPT-5.5 for the hardest research, math and engineering problems, at a steep per-token premium.
OpenAI · Apr 2025
A compact reasoning model that punched far above its price on math — 92.7% on AIME 2025 at $1.10 per million input tokens.
The verdict
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: OpenAI o4-mini works out roughly 35x cheaper per blended million tokens. GPT-5.5 Pro also takes 1M of context versus 200K for OpenAI o4-mini.
Specs & pricing
| GPT-5.5 Pro | OpenAI o4-mini | |
|---|---|---|
| modhub Index | — | 80.9 |
| Input price / 1M | $30 | $1.1 |
| Output price / 1M | $180 | $4.4 |
| Context window | 1M | 200K |
| Max output | 128K | 100K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Jan 2026 | May 2024 |
| Released | Apr 2026 | Apr 2025 |
| Example monthly cost* | $570.00 | $17.60 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, GPT-5.5 Pro or OpenAI o4-mini?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: OpenAI o4-mini works out roughly 35x cheaper per blended million tokens. GPT-5.5 Pro also takes 1M of context versus 200K for OpenAI o4-mini.
- Which is cheaper, GPT-5.5 Pro or OpenAI o4-mini?
- GPT-5.5 Pro costs $30/$180 per million input/output tokens, while OpenAI o4-mini costs $1.1/$4.4. For a typical workload of 10M input and 1.5M output tokens per month, that's $570.00 versus $17.60.
- Which model is better for coding, GPT-5.5 Pro or OpenAI o4-mini?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.