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Gemini 3.7 Flash vs GPT-6 Luna

Compare Gemini 3.7 Flash and GPT-6 Luna side-by-side. See how these vision models stack up in Image Captioning, Open Prompt, Classification, OCR, and Object Detection.

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GoogleGemini 3.7 Flash
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OpenAIGPT-6 Luna
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Models in this comparison

Gemini 3.7 Flash vs GPT-6 Luna on Vision Evals

Gemini 3.7 Flash scores higher on all five Vision Evals tasks.

The widest gap is Reasoning, where Gemini 3.7 Flash leads 80.8% to 64.2%.

Overall, Gemini 3.7 Flash averages 80.1% (#6 of 63) against 69.7% (#21 of 63) for GPT-6 Luna.

GPT-6 Luna is both cheaper ($0.0004 vs $0.0033 per sample) and faster (10.2s vs 11.0s per sample).

Gemini 3.7 FlashGPT-6 Luna

Gemini 3.7 Flash vs GPT-6 Luna Comparison Table

Evals updated October 13, 2026Pricing updated October 16, 2026

PropertyGemini 3.7 FlashGPT-6 Luna
OrganizationGoogleOpenAI
Categoryclosedclosed
Modalitymultimodalmultimodal
Release DateAug 2026Sep 2026
Context Window1.0M1.1M
ParametersUndisclosedUnknown
LicenseProprietaryProprietary
Commercial usecommercial use per vendor termscommercial use per vendor terms
Pricing per 1M tokens
Input $/1M$0.750$0.100
Output $/1M$3.75$0.500
Vision Tasks
CaptioningDemoDemo
Chart Question AnsweringSupportedSupported
ClassificationDemoDemo
Document Question AnsweringSupportedSupported
Image TaggingSupportedSupported
Multi-Label ClassificationSupportedSupported
Object DetectionDemoDemo
OCRDemoDemo
Vision LanguageSupportedSupported
Visual Question AnsweringDemoDemo
Promptable Concept SegmentationNot listedDemo
Model Features
Foundation VisionSupportedSupported
LLMs with Vision CapabilitiesSupportedSupported
Multimodal VisionSupportedSupported
Vision Evalsground-truth scores across 5 vision tasks, pooled at low effort
Overall
80.1%
69.7%
Avg cost / sample$0.0033$0.0004
Avg speed / sample11.04s10.21s
By task
Object Detection (low)
70.5%
±1.1, Mean of 3 runs, range 69.4 to 71.5
$0.0047
65.5%
±0.4, Mean of 3 runs, range 65.2 to 66.0
$0.0006
Object Detection (high)
74.3%
±0.8, Mean of 3 runs, range 73.3 to 75.0
$0.0089
68.0%
±0.7, Mean of 3 runs, range 67.3 to 68.6
$0.0014
Counting (low)
78.4%
±1.4, Mean of 3 runs, range 77.0 to 79.7
$0.0025
71.6%
±0.0, Mean of 3 runs, range 71.6 to 71.6
$0.0002
Counting (high)
79.3%
±2.0, Mean of 3 runs, range 77.0 to 81.1
$0.0056
72.1%
±0.7, Mean of 3 runs, range 71.6 to 73.0
$0.0004
Identification (low)
96.9%
±0.0, Mean of 3 runs, range 96.9 to 96.9
$0.0013
87.5%
±3.1, Mean of 3 runs, range 84.4 to 90.6
$0.0002
Identification (high)
96.9%
±0.0, Mean of 3 runs, range 96.9 to 96.9
$0.0021
87.5%
±3.1, Mean of 3 runs, range 84.4 to 90.6
$0.0002
OCR (low)
73.9%
$0.0032
59.8%
$0.0004
by category
Single value
74.8%
Transcription
91.1%
Structured JSON
86.7%
Text localization
29.4%
Single value
41.7%
Transcription
80.0%
Structured JSON
78.2%
Text localization
47.4%
OCR (high)
78.8%
$0.010
62.5%
$0.0013
by category
Single value
71.7%
Transcription
91.9%
Structured JSON
90.6%
Text localization
59.2%
Single value
44.4%
Transcription
84.0%
Structured JSON
81.0%
Text localization
50.0%
Reasoning (low)
80.8%
±2.0, Mean of 3 runs, range 78.8 to 82.8
$0.0022
64.2%
±3.0, Mean of 3 runs, range 60.3 to 66.2
$0.0003
Reasoning (high)
81.9%
±1.3, Mean of 3 runs, range 80.1 to 82.8
$0.0050
71.1%
±2.3, Mean of 3 runs, range 68.2 to 72.8
$0.0004

Gemini 3.7 Flash vs GPT-6 Luna: Overview

Gemini 3.7 Flash

Gemini 3.7 Flash is a proprietary multimodal model from Google, positioned in the Flash branch of the Gemini 3 series that trades some of the capacity of the larger Pro models for lower latency and lower cost per token. It accepts interleaved text and image input alongside other modalities handled by the Gemini family and returns text, and it continues the series pattern of exposing a configurable thinking budget so that reasoning effort can be scaled up for harder problems or reduced for high throughput extraction, routing and classification work. The model is announced roughly three weeks after Gemini 3.6 Flash, part of an unusually fast iteration cadence within the Flash line.

Google reports gains concentrated in agentic coding and front end generation, citing a WebDev Arena Elo of 1588 for this release compared with 1538 for the preceding Flash model, and describes it as producing more functional layouts and more feature complete applications in fewer prompts. Weights are not published and the architecture, parameter count and training corpus are undisclosed, consistent with prior Gemini releases. Visual capability follows the Flash lineage, covering image and document understanding, chart and diagram interpretation, text recognition in images, and general visual question answering.

GPT-6 Luna

GPT-6 Luna is the fast, cost-efficient tier of OpenAI's GPT-6 model family, sitting below GPT-6 Sol and the larger GPT-6 Astra model that opened the generation. It is a proprietary multimodal transformer that accepts text and image input and returns text, and it exposes an adjustable reasoning effort setting so the same model can run in a low-latency mode or spend additional inference compute on harder problems. OpenAI positions it for high-volume and latency-sensitive workloads such as conversational assistants, classification, and lightweight agentic pipelines, while noting that at higher reasoning effort it handles software engineering and computer-use tasks that previously required a Sol-tier model.

The model supports a context window of roughly 1,050,000 input tokens with a maximum output of 128,000 tokens, which allows long documents, extended agent traces, and large code repositories to be processed in a single request. OpenAI describes the GPT-6 generation as improving factual reliability and adopting a more concise communication style relative to the GPT-5.6 series, and attributes the efficiency of the Sol and Luna tiers to gains in caching and inference rather than to reduced capability. Architecture details, parameter counts, and training data are not published.

Frequently Asked Questions

On Roboflow's Vision Evals, Gemini 3.7 Flash performed better. It scores higher on all five vision tasks and averages 80.1% (#6 of 63) against 69.7% (#21 of 63) for GPT-6 Luna. These scores measure vision capabilities only; either model may perform differently on work outside this benchmark's tasks.

Yes. On the Vision Evals Reasoning benchmark at low effort, Gemini 3.7 Flash leads with 80.8% against 64.2%. This is the widest gap between the two models across the benchmark's tasks.

GPT-6 Luna is cheaper to run. Across Roboflow's Vision Evals task mix it averaged $0.0004 per sample against $0.0033. Gemini 3.7 Flash is priced at $0.75 per 1M input tokens and $3.75 per 1M output; GPT-6 Luna is priced at $0.10 per 1M input tokens and $0.50 per 1M output. Actual costs depend on your image sizes, prompts, and output length.

GPT-6 Luna is faster. Across Roboflow's Vision Evals it averaged 10.2s per inference against 11.0s. Latency varies with image size, prompt length, and provider load, so treat these as relative rather than guaranteed figures.

Yes. The comparison demo on this page runs both models on the same image side by side for image captioning and open prompts in the free Roboflow Playground. You can try it instantly, and a free account unlocks unlimited runs.