GPT-6 Luna vs Nemotron 3 Ultra (550B A55B)
GPT-6 Luna leads the LLM Stats Score 44.5 to 36.2. GPT-6 Luna is 4.6x cheaper per token.
OpenAI · NVIDIA · Updated for 2026
Which is better?
GPT-6 Luna leads the overall LLM Stats Score 44.5 to 36.2, ranking #41 overall.
On price, GPT-6 Luna is roughly 4.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-6 Luna also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-6 Luna
- overall performance matters — it scores 44.5 and ranks #41 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- cost matters — it's about 4.6x cheaper per token
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Sep 2026
Choose Nemotron 3 Ultra (550B A55B)
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
5 reported for GPT-6 Luna · 26 for Nemotron 3 Ultra (550B A55B)
GPT-6 Luna and Nemotron 3 Ultra (550B A55B)don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-6 Luna ($0.10/1M tokens) is 5.0x cheaper than Nemotron 3 Ultra (550B A55B) ($0.50/1M tokens).
For output processing, GPT-6 Luna ($0.50/1M tokens) is 4.4x cheaper than Nemotron 3 Ultra (550B A55B) ($2.20/1M tokens).
In conclusion, Nemotron 3 Ultra (550B A55B) is more expensive than GPT-6 Luna.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-6 Luna accepts 1,050,000 input tokens compared to Nemotron 3 Ultra (550B A55B)'s 262,144 tokens. Nemotron 3 Ultra (550B A55B) can generate longer responses up to 262,144 tokens, while GPT-6 Luna is limited to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
GPT-6 Luna supports multimodal inputs, whereas Nemotron 3 Ultra (550B A55B) does not.
GPT-6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-6 Luna
Nemotron 3 Ultra (550B A55B)
License
Usage and distribution terms
GPT-6 Luna is licensed under a proprietary license, while Nemotron 3 Ultra (550B A55B) uses OpenMDW License v1.1.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
OpenMDW License v1.1
Open weights
Release Timeline
When each model was launched
GPT-6 Luna was released on 2026-09-22, while Nemotron 3 Ultra (550B A55B) was released on 2026-06-04.
GPT-6 Luna is 4 months newer than Nemotron 3 Ultra (550B A55B).
Sep 22, 2026
0 days ago
3mo newerJun 4, 2026
3 months ago
Knowledge Cutoff
When training data ends
GPT-6 Luna has a knowledge cutoff of 2026-05-18, while Nemotron 3 Ultra (550B A55B) has a cutoff of 2025-09-30.
GPT-6 Luna has more recent training data (up to 2026-05-18), making it potentially better informed about events through that date compared to Nemotron 3 Ultra (550B A55B) (2025-09-30).
May 2026
8 mo newerSep 2025
Provider Availability
GPT-6 Luna is available from OpenAI. Nemotron 3 Ultra (550B A55B) is available from DeepInfra.
GPT-6 Luna
Nemotron 3 Ultra (550B A55B)
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-6 Luna and Nemotron 3 Ultra (550B A55B) side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-6 Luna vs Nemotron 3 Ultra (550B A55B).