GPT-6 Luna vs Solar Pro 4
GPT-6 Luna leads the LLM Stats Score 44.5 to 35.1. GPT-6 Luna is 2.6x cheaper per token.
OpenAI · Upstage · Updated for 2026
Which is better?
GPT-6 Luna leads the overall LLM Stats Score 44.5 to 35.1, ranking #41 overall.
On price, GPT-6 Luna is roughly 2.6x 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 2.6x 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 Solar Pro 4
- you want predictable pricing at $0.30/M input and $1.20/M output
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 · 9 for Solar Pro 4
GPT-6 Luna and Solar Pro 4don'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 3.0x cheaper than Solar Pro 4 ($0.30/1M tokens).
For output processing, GPT-6 Luna ($0.50/1M tokens) is 2.4x cheaper than Solar Pro 4 ($1.20/1M tokens).
In conclusion, Solar Pro 4 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 Solar Pro 4's 524,288 tokens. Solar Pro 4 can generate longer responses up to 131,072 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 Solar Pro 4 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
Solar Pro 4
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
GPT-6 Luna was released on 2026-09-22, while Solar Pro 4 was released on 2026-08-06.
GPT-6 Luna is 2 months newer than Solar Pro 4.
Sep 22, 2026
0 days ago
1mo newerAug 6, 2026
1 months ago
Knowledge Cutoff
When training data ends
GPT-6 Luna has a documented knowledge cutoff of 2026-05-18, while Solar Pro 4's cutoff date is not specified.
We can confirm GPT-6 Luna's training data extends to 2026-05-18, but cannot make a direct comparison without Solar Pro 4's cutoff date.
May 2026
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Provider Availability
GPT-6 Luna is available from OpenAI. Solar Pro 4 is available from Upstage.
GPT-6 Luna
Solar Pro 4
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-6 Luna and Solar Pro 4 side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-6 Luna vs Solar Pro 4.