GPT-3.5 Turbo vs GPT-6 Luna
GPT-6 Luna leads the LLM Stats Score 44.5 to -9.4. GPT-6 Luna is 3.8x cheaper per token.
OpenAI · OpenAI · Updated for 2026
Which is better?
GPT-6 Luna leads the overall LLM Stats Score 44.5 to -9.4, ranking #41 overall.
On price, GPT-6 Luna is roughly 3.8x 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-3.5 Turbo
- you want predictable pricing at $0.50/M input and $1.50/M output
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 3.8x 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
At a glance
The differences that matter most.
Individual benchmarks
8 reported for GPT-3.5 Turbo · 5 for GPT-6 Luna
GPT-3.5 Turbo and GPT-6 Lunadon'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-3.5 Turbo ($0.50/1M tokens) is 5.0x more expensive than GPT-6 Luna ($0.10/1M tokens).
For output processing, GPT-3.5 Turbo ($1.50/1M tokens) is 3.0x more expensive than GPT-6 Luna ($0.50/1M tokens).
In conclusion, GPT-3.5 Turbo 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 GPT-3.5 Turbo's 16,385 tokens. GPT-6 Luna can generate longer responses up to 128,000 tokens, while GPT-3.5 Turbo is limited to 4,096 tokens.
Input capabilities
Documented input modalities across available providers
GPT-6 Luna supports multimodal inputs, whereas GPT-3.5 Turbo does not.
GPT-6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-3.5 Turbo
GPT-6 Luna
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-3.5 Turbo was released on 2023-03-21, while GPT-6 Luna was released on 2026-09-22.
GPT-6 Luna is 43 months newer than GPT-3.5 Turbo.
Mar 21, 2023
3.5 years ago
Sep 22, 2026
0 days ago
3.5yr newerKnowledge Cutoff
When training data ends
GPT-3.5 Turbo has a knowledge cutoff of 2021-09-30, while GPT-6 Luna has a cutoff of 2026-05-18.
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 GPT-3.5 Turbo (2021-09-30).
Sep 2021
May 2026
4.7 yr newerProvider Availability
GPT-3.5 Turbo is available from Azure, OpenAI. GPT-6 Luna is available from OpenAI.
GPT-3.5 Turbo
GPT-6 Luna
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-3.5 Turbo and GPT-6 Luna side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-3.5 Turbo vs GPT-6 Luna.