Nano Banana Pro vs GPT-5 Image: Which AI Image Generator Wins in 2025?

The AI image generation landscape has never been more competitive. In late 2025, two models stand at the top: Google's Nano Banana Pro (built on Gemini 3 Pro) and OpenAI's GPT-5 Image. Both deliver stunning results, but they take distinctly different approaches to image generation.

We tested both models head-to-head across photorealism, text rendering, creative composition, and speed. Here's what we found—and which one you should choose depending on your use case.

Quick Comparison Table

Feature	Nano Banana Pro	GPT-5 Image
Company	Google (Gemini 3 Pro)	OpenAI (GPT-5)
Released	November 20, 2025	October 14, 2025
Context Window	65,536 tokens	400,000 tokens
Max Resolution	4K (multiple aspect ratios)	1.5K
Reference Images	Up to 14 images, 5 identities	Limited
Input Price	$2/M tokens	$10/M tokens
Output Price	$12/M tokens	$10/M tokens
Image Output	$0.12/image (1K-2K)	$0.04/image
Speed (1K)	~10-15 seconds	~30-45 seconds
Aspect Ratios	8 options	3 options

Visual Comparison: Ads & Influencer Content

We tested both models with identical prompts across key advertising and influencer content categories. Each test was run with specific aspect ratios matching real-world social media requirements.

Test 1: Product Photography (1:1 Instagram)

Prompt: "Luxury skincare serum bottle on marble surface, soft morning light, water droplets, minimalist aesthetic, product photography for Instagram ad"

Winner: Nano Banana Pro — Superior lighting control and more realistic material rendering on the marble and glass surfaces. The water droplets look more natural.

Test 2: Lifestyle Influencer (4:5 Instagram Feed)

Prompt: "Young woman influencer holding artisan latte in trendy cafe, natural window light, candid lifestyle shot, warm tones, Instagram aesthetic, bokeh background"

Winner: Nano Banana Pro — More authentic skin tones and natural bokeh effect. The overall "Instagram look" is more convincing.

Test 3: Fashion Ad (9:16 Stories/Reels)

Prompt: "Fashion model in elegant summer dress walking on city street, golden hour lighting, full body shot, editorial fashion photography, luxury brand advertisement"

Winner: Tie — Both models deliver editorial-quality results. GPT-5 Image tends toward cleaner compositions while Nano Banana Pro offers more dynamic lighting.

Test 4: Food Photography (1:1)

Prompt: "Gourmet burger with melted cheese and fresh vegetables on wooden board, restaurant food photography, dramatic side lighting, shallow depth of field, appetizing food ad"

Winner: Nano Banana Pro — More appetizing textures and better handling of the melted cheese. The lighting creates more depth and dimension.

Test 5: Tech Product Banner (16:9)

Prompt: "Premium smartphone floating with colorful gradient background, product showcase, sleek modern design, tech advertisement banner, reflections and light rays"

Winner: GPT-5 Image — Cleaner product rendering with more precise reflections. Better suited for tech marketing materials.

Test 6: Beauty/Makeup Ad (4:5)

Prompt: "Close-up beauty portrait of woman with flawless makeup, dewy skin, soft pink lipstick, professional beauty advertisement, studio lighting, cosmetics brand campaign"

Winner: Nano Banana Pro — More realistic skin texture with the "dewy" look cosmetics brands want. Better color accuracy on makeup.

Test 7: Fitness Influencer (9:16 Stories)

Prompt: "Athletic woman in workout gear doing yoga pose outdoors at sunrise, fitness influencer content, activewear brand ad, healthy lifestyle, dynamic composition"

Winner: Nano Banana Pro — More natural body proportions and better handling of the sunrise lighting. The overall composition feels more authentic.

Test 8: Text Rendering - Brand Signage

Prompt: "A vintage coffee shop sign that says MORNING BREW in elegant serif typography, neon lights, rainy night"

Winner: GPT-5 Image — Near-perfect text rendering. Critical for any ad that includes brand names, slogans, or CTAs.

Scorecard: Ads & Influencer Content

Category	Winner	Notes
Product Photography	Nano Banana Pro	Better material rendering
Lifestyle/Influencer	Nano Banana Pro	More authentic look
Fashion Editorial	Tie	Both excel
Food Photography	Nano Banana Pro	More appetizing textures
Tech Products	GPT-5 Image	Cleaner renders
Beauty/Cosmetics	Nano Banana Pro	Better skin rendering
Fitness Content	Nano Banana Pro	More natural bodies
Text/Typography	GPT-5 Image	Perfect text accuracy

Overall for Ads & Influencer Content: Nano Banana Pro wins 5-2-1

For most advertising and influencer use cases, Nano Banana Pro delivers more photorealistic results. However, if your ad includes text (brand names, CTAs, prices), GPT-5 Image is the safer choice for accurate typography.

Nano Banana Pro Overview

Nano Banana Pro is Google's most advanced image-generation and editing model, launched on November 20, 2025 as part of the Gemini 3 Pro family. The name stuck from the viral "Nano Banana" phenomenon that added 13 million users to the Gemini app in just four days when the original version launched in August.

"You went 🍌🍌 for Nano Banana. Now, meet Nano Banana Pro. It's SOTA for image generation + editing with more advanced world knowledge, text rendering, precision + controls." — Sundar Pichai on X

Key Capabilities

• 4K Resolution: Native support for 1K, 2K, and 4K outputs with flexible aspect ratios
• Text Rendering: Industry-leading text in images, including multilingual layouts and long passages
• Identity Preservation: Maintains consistency across up to 5 subjects and 14 reference images
• Multi-Image Blending: Combine up to 14 images while maintaining style consistency
• Search Grounding: Real-time information via Google Search for accurate infographics
• Creative Controls: Localized edits, lighting adjustments, camera transformations, and focus control

GPT-5 Image Overview

GPT-5 Image combines OpenAI's flagship GPT-5 model with state-of-the-art image generation. Released in October 2025, it builds on GPT Image 1's superior instruction following and text rendering, while adding GPT-5's enhanced reasoning capabilities.

On December 16, 2025, OpenAI released GPT Image 1.5, their latest image model that generates images up to 4x faster than its predecessor with improved editing precision.

Key Capabilities

• 400K Context: Massive context window for complex, multi-turn conversations
• File Support: Native support for images, text, and file inputs
• Text Rendering: Strong instruction following for typography and text-heavy images
• Detailed Editing: Precise edits while keeping surrounding details intact
• Fast Iteration: Optimized for quick prototyping and experimentation
• Reasoning: Built-in reasoning for understanding complex prompts

Head-to-Head Comparison

Speed

Nano Banana Pro is significantly faster. According to our testing and third-party benchmarks:

• Nano Banana Pro: 10-15 seconds at 1K resolution, 30-60 seconds at 2K
• GPT-5 Image: 30-45 seconds at 1K, 50-60 seconds at 1.5K

That's roughly a 3x speed advantage for Nano Banana Pro at comparable resolutions.

Resolution & Aspect Ratios

Nano Banana Pro offers more flexibility:

• Nano Banana Pro: 8 aspect ratios, up to 4K resolution
• GPT-5 Image: 3 aspect ratios, up to 1.5K resolution

For professional work requiring high-resolution output, Nano Banana Pro has a clear advantage.

Text Rendering

This is where the models diverge significantly. In our testing with a coffee shop sign that says "MORNING BREW":

• GPT-5 Image: Near-perfect text rendering. Headlines and subheads are accurate with body text around 92% correct.
• Nano Banana Pro: Can produce garbled text like "FASHIÖN MÖNTHLÝ" instead of clean English text in some cases.

For any application involving readable text, GPT-5 Image is currently more reliable, though Nano Banana Pro's text rendering has improved significantly with the Pro version.

Photorealism

Community testing and Reddit discussions consistently favor Nano Banana Pro for pure photorealism:

• Nano Banana Pro: Ultra-clean, highly realistic results with better skin tones, camera realism, and fine surface detail
• GPT-5 Image: Strong results but occasionally falls into "AI look" territory

One viral comparison noted: "The Nano Banana Pro picture on the left is scarily realistic."

LMArena Benchmark

In the LMArena blind comparison rankings, results are close:

• GPT Image 1.5 took first place, edging out Nano Banana Pro
• Nano Banana dominates in character generation (1,170 vs 1,060) and creative tasks (1,120 vs 1,060)
• GPT-4o wins in stylization (1,190 vs 1,070)

Pricing Comparison

Pricing differs significantly between the two approaches:

Model	Input (per M tokens)	Output (per M tokens)	Image Output
Nano Banana Pro	$2.00	$12.00	$0.12-0.24/image
GPT-5 Image	$10.00	$10.00	$0.04/image

GPT-5 Image has lower per-image costs ($0.04 vs $0.12-0.24), but Nano Banana Pro's faster generation and higher resolution may provide better value for professional workflows requiring fewer iterations.

When to Use Each Model

Choose Nano Banana Pro When:

• You need high-resolution output (2K-4K images)
• Photorealism is your top priority
• You're working on product visualization, storyboarding, or professional design
• You need consistent identity across multiple images (characters, branding)
• Speed matters—you need fast iterations
• You're creating infographics with real-time data (via Search grounding)

Choose GPT-5 Image When:

• Text accuracy is critical (signage, typography, marketing materials)
• You need precise instruction following for specific layouts
• You're doing iterative editing on existing images
• Budget is a concern (lower per-image cost)
• You need the massive 400K context window for complex multi-turn work
• You're prototyping and need quick experimentation

The Verdict

Both models are exceptional, and the "best" choice depends on your specific needs:

• For raw image quality and photorealism: Nano Banana Pro wins
• For text-heavy images and precise instruction following: GPT-5 Image wins
• For speed and resolution: Nano Banana Pro wins
• For cost-sensitive high-volume work: GPT-5 Image wins

The smartest approach for professional work? Use both. Prototype with GPT-5 Image for its speed and instruction following, then finalize with Nano Banana Pro for the highest quality renders.

Try Both on Writingmate

The good news is you don't have to choose. Both Nano Banana Pro and GPT-5 Image are available on Writingmate through our OpenRouter integration. With your subscription, you get access to 200+ AI models—including both of these image generation powerhouses—all in one place.

To try them:

1. Open Writingmate and start a new chat
2. Select Nano Banana Pro or GPT-5 Image from the model dropdown
3. Start generating images

Compare them side by side and find the perfect tool for your creative workflow.