AI model comparison

GPT-6 Luna vs Gemma 4 26B A4B

Side by side comparison of GPT-6 Luna and Gemma 4 26B A4B on pricing, benchmark scores, context window, and more.

GPT-6 Luna is the fast, cost-efficient model in OpenAI's GPT-6 series, positioned below GPT-6 Sol.

Input / 1M: $0.10
Output / 1M: $0.50
Context: 1.05M

Gemma 4 26B A4B IT is an instruction-tuned Mixture-of-Experts (MoE) model from Google DeepMind.

Input / 1M: $0.09
Output / 1M: $0.30
Context: 262K

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At a glance

Quick verdict

How the two models stack up on the things people ask about most.

Lower price

Gemma 4 26B A4B

1.4x cheaper for a typical chat

Higher intelligence score

Not available

Not enough benchmark data

Larger context window

GPT-6 Luna

1.05M vs 262K tokens

Newer release

GPT-6 Luna

Released September 22, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

GPT-6 Luna27.8

Gemma 4 26B A4BNot available

Coding index

GPT-6 LunaNot available

Gemma 4 26B A4B39.3

Agentic index

GPT-6 LunaNot available

Gemma 4 26B A4B2.9

Pricing

GPT-6 Luna vs Gemma 4 26B A4B API pricing

Per-token API rates. Cheaper option highlighted.

Metric	GPT-6 Luna	Gemma 4 26B A4B
Input tokensPer 1M tokens	$0.10	$0.09
Output tokensPer 1M tokens	$0.50	$0.30
Cached input (read)Per 1M tokens	$0.01	$0.05
Cache writePer 1M tokens	$0.13	Not available
Long-context pricingPer 1M tokens, for very long prompts	$0.20 in / $0.75 out above 272K	Same rate at any length
Web searchPer request	$0.01	Not available

What it costs in practice

Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.

Chat message

2K in, 500 out

GPT-6 Luna$0.45

Gemma 4 26B A4B$0.33

Coding task

30K in, 4K out

GPT-6 Luna$5$2.30 cached

Gemma 4 26B A4B$3.90$2.70 cached

Long document summary

150K in, 2K out

GPT-6 Luna$16$2.50 cached

Gemma 4 26B A4B$14.10$8.10 cached

Specs

Context window and capabilities

How much each model can read, how much it can write, and what it accepts as input.

Metric	GPT-6 Luna	Gemma 4 26B A4B
Context window	1.05M tokens	262K tokens
Max output	128K tokens	236K tokens
Input types	File, Image, Text	Image, Text, Video
Output types	Text	Text
Reasoning effort levels	Max, Extra high, High, Medium, Low, None	Not available
Default reasoning effort	Medium	Not available
Release date	September 22, 2026	April 3, 2026

Features

Supported features

API features available for each model.

Metric	GPT-6 Luna	Gemma 4 26B A4B
Tool calling	Supported	Supported
Structured outputs	Supported	Supported
JSON mode	Supported	Supported
Reasoning	Supported	Supported
Temperature	Not supported	Supported
Stop sequences	Not supported	Supported
Deterministic seed	Supported	Supported
Verbosity control	Supported	Not supported

Our take

Gemma 4 26B A4B is 1.4x cheaper for a typical chat. GPT-6 Luna has the larger context window (1.05M vs 262K tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.

FAQ

Frequently asked questions

Is GPT-6 Luna or Gemma 4 26B A4B cheaper?

Gemma 4 26B A4B is cheaper for a typical chat (2K input tokens and 500 output tokens). Gemma 4 26B A4B costs $0.09 per 1M input tokens and $0.30 per 1M output tokens, while GPT-6 Luna costs $0.10 per 1M input tokens and $0.50 per 1M output tokens.

Which has a bigger context window, GPT-6 Luna or Gemma 4 26B A4B?

GPT-6 Luna supports up to 1.05M tokens of context, compared with 262K for Gemma 4 26B A4B.

Can I use GPT-6 Luna and Gemma 4 26B A4B at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-6 Luna and Gemma 4 26B A4B answer side by side and keep the better response.

Why choose? Ask both.

Send one prompt to GPT-6 Luna and Gemma 4 26B A4B at the same time. Compare the answers side by side and keep the best one.

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