Model comparison

GPT-6 Sol vs GPT-6 Luna

GPT-6 Sol and GPT-6 Luna were released together and share the same 1.05M-token context window. Sol is the stronger reasoner at 20 times Luna's input price; Luna is the fast, cheap model for everyday work and has the newer knowledge cutoff.

Try both in AimiChat
GPT-6 Sol
OpenAI · $2 input / $10 output per 1M tokens
GPT-6 Luna
OpenAI · $0.10 input / $0.50 output per 1M tokens

The short answer

Pick GPT-6 Sol forHard analysis and planning
Pick GPT-6 Luna forQuick questions and rewrites
In AimiChatAimi Ultra / Free

GPT-6 Sol vs GPT-6 Luna: specs side by side

GPT-6 SolGPT-6 Luna
Made byOpenAIOpenAI
ReleasedSeptember 22, 2026September 22, 2026
API model IDgpt-6-solgpt-6-luna
Context window1.05M tokens (922K input)1.05M tokens (922K input)
Max output128,000 tokens128,000 tokens
Knowledge cutoffApril 20, 2026May 18, 2026
InputsText and imagesText and images
API price$2 input / $10 output per 1M tokens$0.10 input / $0.50 output per 1M tokens
In AimiChatPremium quality · Aimi Ultra ($50/month)Fast quality · Free ($0)

Which to use for each task

GPT-6 Luna

Quick questions and rewrites

Luna is built for speed and is included free in AimiChat.

GPT-6 Sol

Hard analysis and planning

Sol is built for demanding reasoning where Luna may miss a step.

GPT-6 Sol

Coding beyond small snippets

Sol scores higher on OpenAI's reported coding benchmark (68.8% vs 66.6% on DeepSWE v1.1 at max effort) and handles longer tasks better.

GPT-6 Luna

Summaries and extraction

Luna is designed for exactly this kind of repeatable work, at a fraction of the cost.

What to know before you choose

On OpenAI's reported DeepSWE v1.1 results the gap is small (68.8% for Sol vs 66.6% for Luna, both at max effort), which is why Luna is good enough for many everyday coding questions.

In AimiChat, GPT-6 Luna is on the Free plan and GPT-6 Sol is available from the Aimi Ultra plan.

Published benchmarks

Each company reports different tests with different settings, so these are listed per model rather than head to head.

ModelBenchmarkScoreReported by
GPT-6 SolDeepSWE v1.1 (max effort)68.8%OpenAI launch post, as reported by VentureBeat and Codersera
GPT-6 SolOSWorld 2.0 offline (xhigh effort)60.5%OpenAI launch post, as reported by VentureBeat and Codersera
GPT-6 LunaDeepSWE v1.1 (max effort)66.6%OpenAI launch post, as reported by VentureBeat and Codersera

Try both in AimiChat

GPT-6 Sol runs on the Premium quality and GPT-6 Luna on Fast. On a plan that includes both, you can send the same prompt twice in one chat, switching quality in between, and compare the answers directly. Read more about GPT-6 Sol and GPT-6 Luna, or see which plan includes which model.

Sources

Sources checked · September 24, 2026

Specifications and prices come from the model makers and API listings below. Benchmark figures are reported by the company that made the model and are not independent tests.