---
title: "Cheaper alternatives to GPT-5.6 Luna · Undominated.ai"
canonical: https://undominated.ai/alternatives/openai__gpt-5.6-luna/
description: "5 models score at least as high as GPT-5.6 Luna and cost no more on a balanced workload. 0 give up nothing measurable; the other 5 name what they drop. Measured prices and independent scores."
---

# Cheaper alternatives to GPT-5.6 Luna · Undominated.ai

> 5 models score at least as high as GPT-5.6 Luna and cost no more on a balanced workload. 0 give up nothing measurable; the other 5 name what they drop. Measured prices and independent scores.

# Cheaper alternatives to GPT-5.6 Luna

OpenAI · LMArena 1428.5 · $0.450/M on a balanced workload · prices as of 2026-08-28

## Everything cheaper and higher-scoring gives something up.

Of the 133 models carrying both an independent score and a published price at the same delivery mode, **5** score at least as high as GPT-5.6 Luna and cost no more under at least one workload. **5** do not, and every row names what it drops.

Dominance is not a property of a model. It is a property of a model, a capability lens and a workload, and all three are named on every row. Scores are LMArena Elo, used under CC BY 4.0 from the official dataset; prices are blended per million tokens. A higher score is not a drop-in replacement.

This page is built from that comparison and nothing else. When no model is both better and cheaper than GPT-5.6 Luna, it is not generated.

## Where it holds

| Workload | GPT-5.6 Luna $/M | Better and cheaper | With a trade |
| --- | --- | --- | --- |
| Balanced | $0.450 | 0 | 4 |
| Summarise | $0.199 | 0 | 4 |
| Chat | $0.546 | 0 | 5 |
| Code gen | $0.786 | 0 | 5 |
| Agentic | $0.243 | 0 | 4 |

Workload mixes are defined on the [methodology page](/methodology/). Cached input is priced at the cached rate, and reasoning tokens at the worse of the reasoning and output rates.

## What you would be replacing

| Intelligence | 1428.5 |
| --- | --- |
| Context window | 1.1M |
| Max output | 128K |
| Input modes | file, image, text |
| Tool use | yes |
| Extended reasoning | yes |

A replacement has to clear every line above, not just the score. [Full record for GPT-5.6 Luna](/models/openai__gpt-5.6-luna/).

## Cheaper and higher-scoring, but you give something up 5

These score at least as high and cost no more on the two plotted axes, and lose something that is not on them. Read the last column before switching.

| Model | Intelligence | $/M | Holds under | What you give up |
| --- | --- | --- | --- | --- |
| Gemma 4 31B Google | 1441.7 +13.2 | $0.152 | Balanced −66% Summarise −54% Chat −67% Code gen −70% Agentic −57% | 1.1M → 262K context 128K → 16K max output no file input |
| Hy3 Tencent | 1441.2 +12.7 | $0.144 | Balanced −68% Summarise −61% Chat −70% Code gen −71% Agentic −66% | 1.1M → 262K context no file, image input |
| Gemma 4 26B A4B Google | 1434.6 tie | $0.138 | Balanced −69% Summarise −58% Chat −67% Code gen −70% Agentic −55% | 1.1M → 262K context 128K → 16K max output no file input |
| DeepSeek V4 Flash 0423 DeepSeek | 1431.6 tie | $0.101 | Balanced −77% Summarise −66% Chat −83% Code gen −84% Agentic −78% | 1.1M → 1.0M context no file, image input |
| MiMo-V2.5-Pro Xiaomi | 1465 +36.5 | $0.480 chat | Chat −12% Code gen −16% | no file, image input |

## What this compares, and what it leaves out

 - Quality is LMArena Elo, used under CC BY 4.0 from the official dataset. The 95% confidence interval on a difference between two scores is about ±10.68 points, so a gap smaller than that is marked *tie* rather than an improvement — see [significance bands](/significance/).
 - 188 further models at this delivery mode carry a price but no independent score. They are absent from the comparison in both directions — unrated is not a zero, and an unmeasured model is neither an alternative nor a worse buy.
 - Retired models are never offered as an alternative, and a model only competes against its own delivery mode: batch trades latency for price, so it is not a like-for-like swap.
 - Nothing here measures latency, throughput, rate limits or how a model behaves on your prompts. Two models with the same index score are not interchangeable.
 - The models that nothing beats on both axes are on the [value frontier](/frontier/), and every other model something cheaper beats is [listed here](/alternatives/).