AI model comparison

GPT-6 Luna vs DeepSeek V4 Flash Vision Exp

Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.

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

DeepSeek V4 Flash Vision Exp is an experimental vision-enabled version of [DeepSeek V4 Flash 0731](https://openrouter.ai/deepseek/deepseek-v4-flash-0731) from DeepSeek, adding image understanding while matching the base model on text capabilities including agents,

Input / 1M
$0.22
Output / 1M
$0.65
Context
1.05M

At a glance

Quick verdict

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

Lower price

openai logo

GPT-6 Luna

1.7x cheaper for a typical chat

Higher intelligence score

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GPT-6 Luna

38.1 vs 34.8 on Artificial Analysis

Larger context window

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GPT-6 Luna

1.05M vs 1.05M tokens

Newer release

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GPT-6 Luna

Released September 22, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

openai logoGPT-6 Luna38.1
deepseek logoDeepSeek V4 Flash Vision Exp34.8

Coding index

openai logoGPT-6 LunaNot available
deepseek logoDeepSeek V4 Flash Vision Exp65

Agentic index

openai logoGPT-6 LunaNot available
deepseek logoDeepSeek V4 Flash Vision Exp47.5

Pricing

GPT-6 Luna vs DeepSeek V4 Flash Vision Exp API pricing

Per-token API rates. Cheaper option highlighted.

Metricopenai logoGPT-6 Lunadeepseek logoDeepSeek V4 Flash Vision Exp
Input tokensPer 1M tokens$0.10$0.22
Output tokensPer 1M tokens$0.50$0.65
Cached input (read)Per 1M tokens$0.01$0.01
Cache writePer 1M tokens$0.13Not available
Long-context pricingPer 1M tokens, for very long prompts$0.20 in / $0.75 out above 272KSame rate at any length
Web searchPer request$0.01Not 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

openai logoGPT-6 Luna$0.45
deepseek logoDeepSeek V4 Flash Vision Exp$0.75

Coding task

30K in, 4K out

openai logoGPT-6 Luna$5$2.30 cached
deepseek logoDeepSeek V4 Flash Vision Exp$9.06$2.79 cached

Long document summary

150K in, 2K out

openai logoGPT-6 Luna$16$2.50 cached
deepseek logoDeepSeek V4 Flash Vision Exp$33.63$2.32 cached

Specs

Context window and capabilities

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

Metricopenai logoGPT-6 Lunadeepseek logoDeepSeek V4 Flash Vision Exp
Context window1.05M tokens1.05M tokens
Max output128K tokens262K tokens
Input typesFile, Image, TextImage, Text
Output typesTextText
Reasoning effort levelsMax, Extra high, High, Medium, Low, NoneMax, High, Low
Default reasoning effortMediumHigh
Release dateSeptember 22, 2026August 21, 2026

Features

Supported features

API features available for each model.

Metricopenai logoGPT-6 Lunadeepseek logoDeepSeek V4 Flash Vision Exp
Tool callingSupportedSupported
Structured outputsSupportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureNot supportedSupported
Stop sequencesNot supportedSupported
Deterministic seedSupportedSupported
Verbosity controlSupportedNot supported

Our take

GPT-6 Luna is 1.7x cheaper for a typical chat. GPT-6 Luna scores higher on the Artificial Analysis Intelligence Index (38.1 vs 34.8). GPT-6 Luna has the larger context window (1.05M vs 1.05M 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 DeepSeek V4 Flash Vision Exp cheaper?

GPT-6 Luna is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-6 Luna costs $0.10 per 1M input tokens and $0.50 per 1M output tokens, while DeepSeek V4 Flash Vision Exp costs $0.22 per 1M input tokens and $0.65 per 1M output tokens.

Which has a bigger context window, GPT-6 Luna or DeepSeek V4 Flash Vision Exp?

GPT-6 Luna supports up to 1.05M tokens of context, compared with 1.05M for DeepSeek V4 Flash Vision Exp.

Is GPT-6 Luna smarter than DeepSeek V4 Flash Vision Exp?

On the Artificial Analysis Intelligence Index, GPT-6 Luna scores 38.1 and DeepSeek V4 Flash Vision Exp scores 34.8, putting GPT-6 Luna ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.

Can I use GPT-6 Luna and DeepSeek V4 Flash Vision Exp at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-6 Luna and DeepSeek V4 Flash Vision Exp answer side by side and keep the better response.

openai logodeepseek logo

Why choose? Ask both.

Send one prompt to GPT-6 Luna and DeepSeek V4 Flash Vision Exp at the same time. Compare the answers side by side and keep the best one.