# Nemotron 3 Ultra 550B A55B vs Step 5 Preview - AI Model Comparison

- Page: https://opencode.ai/data/compare/nvidia/nemotron-3-ultra-550b-a55b/stepfun/step-5-preview
- Updated: 2026-10-22T18:10:53.000Z

|  | Nemotron 3 Ultra 550B A55B | Step 5 Preview |
| --- | --- | --- |
| Lab | NVIDIA | StepFun |
| Context window | 1M | 1M |
| Max output | 128K | 1M |
| Input modalities | text | text, image, video |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| Open weights | Yes | Yes |
| Release date | 2026-06-04 | 2026-09-16 |
| Input price per 1M tokens | $0.60 | $1.00 |
| Output price per 1M tokens | $2.40 | $2.70 |
| Cached input price per 1M tokens | $0.12 | $0.05 |
| OpenCode tokens: past 2 months | 0 | 7.2T |
| Share of all tokens | 0% | 0.6% |
| Rank by tokens last week | - | #19 |
| Unique users | 0 | 112K |
| Weekly retention | - | 77.1% |

Model pages: [Nemotron 3 Ultra 550B A55B](https://opencode.ai/data/nvidia/nemotron-3-ultra-550b-a55b.md), [Step 5 Preview](https://opencode.ai/data/stepfun/step-5-preview.md)

## Methodology

- Updates: Aggregated every hour. Days and weeks use UTC.
- Tokens: Input, output, reasoning, and cached tokens for each request.
- Users and sessions: Approximate counts of distinct users and OpenCode sessions.
- Cost: Session cost is the average cost per OpenCode session. Token prices are list prices from the OpenCode model catalog.
- Retention: The share of a model's users in one week who use it again the next week.
- Citation: Cite OpenCode Data (opencode.ai/data) with the update time shown at the top of the page.