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GPT-6 Luna vs Qwen3.5-27B

GPT-6 Luna averages 69.7% across five Vision Evals tasks and Qwen3.5-27B 64.1% across four (#22 and #32 of 65 models), so GPT-6 Luna leads overall.

  • GPT-6 Luna wins all 4 tasks both ran, with its widest lead on object detection (65.5% vs 50.5%).
  • GPT-6 Luna is about 1/10 of the cost: $0.0004 vs $0.0043 overall average cost per sample.
  • GPT-6 Luna is faster: 10.2s vs 80.4s per sample.

Compare GPT-6 Luna vs Qwen3.5-27B live

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OpenAIGPT-6 Luna
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QwenQwen3.5-27B
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GPT-6 Luna vs Qwen3.5-27B on Vision Evals

Score by taskGPT-6 LunaQwen3.5-27B
Object Detection
65.5
50.5
Identification
87.5
80.2
Reasoning
64.2
58.1
Counting
71.6
67.6

Roboflow Vision Evals. Full breakdown below.

GPT-6 Luna vs Qwen3.5-27B Comparison Table

Evals updated October 26, 2026Pricing updated November 6, 2026

PropertyGPT-6 LunaQwen3.5-27B
OrganizationOpenAIQwen
Categoryclosedopen
Modalitymultimodalmultimodal
Release DateSep 2026Feb 2026
Context Window1.1M262K
ParametersUnknown27B
LicenseProprietaryApache 2.0
Commercial usecommercial use per vendor termsfree for commercial use
Pricing per 1M tokens
Input $/1M$0.100$0.260
Output $/1M$0.500$2.60
Vision Tasks
Promptable Concept SegmentationDemoNot listed
Both support 10 more tasks
Model Features
Both support 3 more features
Vision Evalsground-truth scores across 5 vision tasks, pooled at low effort
Overall
69.7%
64.1%*
Quantizationsself-hosted
BF1664.1%FP860.9%AWQ-INT461.2%hardware →
Avg cost / sample$0.0004$0.0043
Avg speed / sample10.21s80.37s
By task
Object Detection (low)
65.5%
±0.4, Mean of 3 runs, range 65.2 to 66.0
$0.0006
50.5%
±3.5, Mean of 3 runs, range 46.1 to 53.0
$0
Object Detection (high)
68.0%
±0.7, Mean of 3 runs, range 67.3 to 68.6
$0.0014
–
Counting (low)
71.6%
±0.0, Mean of 3 runs, range 71.6 to 71.6
$0.0002
67.6%
±1.4, Mean of 3 runs, range 66.2 to 68.9
$0
Counting (high)
72.1%
±0.7, Mean of 3 runs, range 71.6 to 73.0
$0.0004
–
Identification (low)
87.5%
±3.1, Mean of 3 runs, range 84.4 to 90.6
$0.0002
80.2%
±4.7, Mean of 3 runs, range 75.0 to 84.4
$0
Identification (high)
87.5%
±3.1, Mean of 3 runs, range 84.4 to 90.6
$0.0002
–
OCR (low)
59.8%
$0.0004
–
by category
Single value
41.7%
Transcription
80.0%
Structured JSON
78.2%
Text localization
47.4%
OCR (high)
62.5%
$0.0013
–
by category
Single value
44.4%
Transcription
84.0%
Structured JSON
81.0%
Text localization
50.0%
Reasoning (low)
64.2%
±3.0, Mean of 3 runs, range 60.3 to 66.2
$0.0003
58.1%
±2.3, Mean of 3 runs, range 55.6 to 60.3
$0
Reasoning (high)
71.1%
±2.3, Mean of 3 runs, range 68.2 to 72.8
$0.0004
–

GPT-6 Luna vs Qwen3.5-27B: Overview

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.

Qwen3.5-27B

Qwen3.5-27B is a multimodal dense hybrid model developed by Alibaba Cloud’s Qwen team and released in February 2026 as a high-precision entry in the Qwen3.5 "Medium" series. Unlike its Mixture-of-Experts (MoE) siblings, the 27B model utilizes a dense architecture combining Gated Delta Networks with a feed-forward structure, activating its full parameter suite for every inference to maximize reliability. The model features a native 262K-token context window, extensible to 1M tokens via YaRN (RoPE scaling), and is released under the Apache-2.0 license.

Optimized for agentic workflows, Qwen3.5-27B employs an early-fusion architecture that treats visual and textual data as a unified stream for deep cross-modal reasoning. While the larger MoE variants in the family lead in raw knowledge benchmarks, the 27B model offers a stable and high-density alternative for structured data extraction and spatial perception, contributing to the Qwen3.5 family’s generational leap in OCR accuracy over the previous Qwen3-VL series.

Frequently Asked Questions

On Roboflow's Vision Evals, GPT-6 Luna performed better. It scores higher on all 4 vision tasks and averages 69.7% (#22 of 65) against 64.1% (#32 of 65) for Qwen3.5-27B. These scores measure vision capabilities only; either model may perform differently on work outside this benchmark's tasks.

Yes. On the Vision Evals Object Detection benchmark at low effort, GPT-6 Luna leads with 65.5% against 50.5%. 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 $0.0043. 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 80.4s. 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 OCR in the free Roboflow Playground. You can try it instantly, and a free account unlocks unlimited runs.