Model Comparison

Flux 2 Dev vs Flux 2 Pro

Comparing two tiers of the same generation: the open-weight Flux 2 Dev against the proprietary Flux 2 Pro. We analyze when the premium model justifies its higher cost, and when Dev delivers more than enough quality.

Comparison8 min read
Background

Same Generation, Different Tiers

Black Forest Labs released Flux 2 Dev and Flux 2 Pro simultaneously in January 2025, offering developers a clear choice: excellent quality at a reasonable price, or premium quality for those who need the absolute best. Unlike the Schnell vs Dev comparison where speed is the primary trade-off, here both models are relatively slow—the difference is purely about output quality.

Flux 2 Dev is the open-weight version, meaning its weights are publicly available for researchers and developers to fine-tune and customize. Flux 2 Pro is proprietary and closed-source, with Black Forest Labs retaining exclusive control over the model. This distinction matters less for API users—both models are accessed the same way—but it explains why Pro can achieve slightly higher quality while keeping certain optimizations private.

The cost difference is substantial: Pro costs about 2.5x more than Dev. That's a significant premium for what benchmarks suggest is a modest quality improvement. The ELO gap (~1143 for Dev vs ~1170 for Pro) confirms this—both are strong performers, but Pro edges ahead in blind comparisons.

Both models support image-to-image generation and produce excellent prompt adherence. The practical question is whether Pro's refinements in detail, coherence, and color accuracy justify the premium for your specific use case.

Note: Both models are available through ImageGPT's quality routes. Flux 2 Dev anchors the "quality/balanced" route, while Flux 2 Pro appears in the "quality/high" route for maximum quality.

Side by Side

Visual Comparison

Compare outputs from both models using identical prompts. Look for differences in fine detail, color richness, and overall coherence.

PromptFlux 2 DevFlux 2 Pro
PortraitClose-up portrait of an elderly fisherman with weathered skin, deep wrinkles, piercing blue eyes, natural lighting
Flux 2 Dev - Portrait
Model: flux-2-dev
Close-up portrait of an elderly fisherman with weathered skin, deep wrinkles, piercing blue eyes, natural lighting
Flux 2 Pro - Portrait
Model: flux-2-pro
Close-up portrait of an elderly fisherman with weathered skin, deep wrinkles, piercing blue eyes, natural lighting
LandscapeDramatic mountain valley at sunset, snow-capped peaks, winding river, volumetric fog, cinematic composition
Flux 2 Dev - Landscape
Model: flux-2-dev
Dramatic mountain valley at sunset, snow-capped peaks, winding river, volumetric fog, cinematic composition
Flux 2 Pro - Landscape
Model: flux-2-pro
Dramatic mountain valley at sunset, snow-capped peaks, winding river, volumetric fog, cinematic composition
TextA rustic wooden sign that says "FRESH BREAD" hanging outside a French bakery, morning light
Flux 2 Dev - Text
Model: flux-2-dev
A rustic wooden sign that says "FRESH BREAD" hanging outside a French bakery, morning light
Flux 2 Pro - Text
Model: flux-2-pro
A rustic wooden sign that says "FRESH BREAD" hanging outside a French bakery, morning light
ProductLuxury perfume bottle on a marble surface, dramatic studio lighting, reflection, minimalist composition, 4K product photography
Flux 2 Dev - Product
Model: flux-2-dev
Luxury perfume bottle on a marble surface, dramatic studio lighting, reflection, minimalist composition, 4K product photography
Flux 2 Pro - Product
Model: flux-2-pro
Luxury perfume bottle on a marble surface, dramatic studio lighting, reflection, minimalist composition, 4K product photography
ArchitectureModern minimalist house with floor-to-ceiling windows, surrounded by forest, golden hour, architectural photography
Flux 2 Dev - Architecture
Model: flux-2-dev
Modern minimalist house with floor-to-ceiling windows, surrounded by forest, golden hour, architectural photography
Flux 2 Pro - Architecture
Model: flux-2-pro
Modern minimalist house with floor-to-ceiling windows, surrounded by forest, golden hour, architectural photography

New to ImageGPT?

ImageGPT is the easiest way to add custom images to your site, app, or agent. Access both Flux 2 Dev and Flux 2 Pro through a single img tag—no need to manage different providers or API keys. Start with a 7-day free trial.

Recommendations

When to Use Each Model

Each model serves different needs. Choose based on your quality requirements and budget constraints.

Flux 2 Dev

  • Production workflows with consistent quality needs
  • When budget matters but you still need professional results
  • Iterating on concepts before finalizing
  • Bulk generation for content libraries
  • When 'excellent' quality is sufficient

Flux 2 Pro

  • Hero images and key marketing visuals
  • Print materials requiring maximum detail
  • Premium product photography
  • When clients specifically require best-available quality
  • Final versions after iterating with Dev
Deep Dive

Fine Detail & Micro-Texture

Examining how each model renders subtle details like skin pores, fabric weave, and surface imperfections.

Flux 2 Dev
"Extreme macro photograph of a dragonfly wing, showing cellul..."
Flux 2 Dev result
Model: flux-2-dev
Extreme macro photograph of a dragonfly wing, showing cellular structure, iridescent membrane, veins, morning dew droplets, natural lighting, scientific detail
Flux 2 Pro
"Extreme macro photograph of a dragonfly wing, showing cellul..."
Flux 2 Pro result
Model: flux-2-pro
Extreme macro photograph of a dragonfly wing, showing cellular structure, iridescent membrane, veins, morning dew droplets, natural lighting, scientific detail

Micro-texture is where premium models typically justify their cost. This prompt demands precise rendering of the dragonfly wing's cellular structure—hexagonal patterns, delicate veins, and light refraction through dewdrops. These details require the model to maintain coherence at multiple scales simultaneously.

In our testing, Flux 2 Pro tended to produce slightly sharper cellular boundaries and more convincing iridescence. The difference was subtle but consistent—Pro images often held up better under close inspection. For images that will be viewed at smaller sizes, this distinction may not matter. For large prints or detailed examination, Pro's refinements become more apparent.

Tip: For web thumbnails and social media, Dev's quality is typically sufficient. Reserve Pro for hero images and print materials.

Deep Dive

Color Accuracy & Tonal Range

Comparing how each model handles complex color palettes and subtle tonal gradations.

Flux 2 Dev
"Still life painting of a bowl of mixed fruits - red apples, ..."
Flux 2 Dev result
Model: flux-2-dev
Still life painting of a bowl of mixed fruits - red apples, yellow lemons, purple grapes, orange tangerines - on a wooden table, Flemish old master style, dramatic chiaroscuro lighting, oil paint texture
Flux 2 Pro
"Still life painting of a bowl of mixed fruits - red apples, ..."
Flux 2 Pro result
Model: flux-2-pro
Still life painting of a bowl of mixed fruits - red apples, yellow lemons, purple grapes, orange tangerines - on a wooden table, Flemish old master style, dramatic chiaroscuro lighting, oil paint texture

This prompt tests color accuracy across a range of hues while also demanding the subtle tonal gradations of chiaroscuro lighting—the dramatic interplay of light and shadow that defined old master paintings. Models need to balance saturated fruit colors against deep shadows without losing detail in either extreme.

We observed that Flux 2 Pro tended to produce richer shadow detail and more nuanced color transitions. Dev sometimes clipped shadows more aggressively or produced slightly less saturated highlights. The difference was most noticeable in the shadow regions where Pro maintained more visible texture and form. For product photography and artistic work where color precision matters, Pro offers a slight advantage.

Note: For product photography where color accuracy is critical, Pro's better tonal handling may justify the premium—especially for items like jewelry or fashion.

Deep Dive

Compositional Coherence

Testing how well each model maintains logical consistency across complex scenes.

Flux 2 Dev
"A cozy library interior with floor-to-ceiling bookshelves, l..."
Flux 2 Dev result
Model: flux-2-dev
A cozy library interior with floor-to-ceiling bookshelves, leather armchair by a fireplace, warm reading lamp, Persian rug, rain visible through tall windows, afternoon light mixing with lamp glow
Flux 2 Pro
"A cozy library interior with floor-to-ceiling bookshelves, l..."
Flux 2 Pro result
Model: flux-2-pro
A cozy library interior with floor-to-ceiling bookshelves, leather armchair by a fireplace, warm reading lamp, Persian rug, rain visible through tall windows, afternoon light mixing with lamp glow

Complex interior scenes require models to maintain spatial logic—where light sources are positioned, how shadows fall, how objects relate to each other. This prompt includes multiple light sources (fireplace, reading lamp, window light) and numerous elements that must coexist believably in the same space.

Both models handled this well, which is expected given their similar architectures. Where Pro showed advantages was in subtle coherence details: consistent shadow directions, more believable light falloff, and slightly better handling of reflective surfaces like polished wood or leather. These differences are the kind that viewers feel rather than consciously notice—the image just "works" better.

Deep Dive

Photorealistic Portraits

Evaluating how each model handles human faces—the most scrutinized subject in image generation.

Flux 2 Dev
"Professional headshot of a middle-aged businesswoman, confid..."
Flux 2 Dev result
Model: flux-2-dev
Professional headshot of a middle-aged businesswoman, confident expression, subtle smile, studio lighting with soft fill, neutral gray background, shallow depth of field, corporate portrait style
Flux 2 Pro
"Professional headshot of a middle-aged businesswoman, confid..."
Flux 2 Pro result
Model: flux-2-pro
Professional headshot of a middle-aged businesswoman, confident expression, subtle smile, studio lighting with soft fill, neutral gray background, shallow depth of field, corporate portrait style

Portraits are where AI generation is most heavily scrutinized. Viewers are experts at detecting unnatural faces—we've evolved to read faces intently. Subtle issues with eye alignment, skin texture, or facial symmetry immediately register as "wrong" even if we can't articulate why.

In portrait comparisons, both models produced professional-quality results. Pro showed marginally better skin rendering—more natural pores and subsurface scattering effects that make skin look like skin rather than plastic. Eye catchlights and iris detail also tended to be slightly more refined. For stock photography or professional use, these small improvements may matter; for social media or web thumbnails, Dev delivers comparable results.

Tip: For portraits that will be used at large sizes or in professional contexts, Pro's refinements in skin and eye rendering are worth the premium.

Deep Dive

The Value Calculation

When does paying 2.5x more actually make sense?

Dev (~2.5s)
"Luxury watch product photo, stainless steel case, leather st..."
Dev (~2.5s) result
Model: flux-2-dev
Luxury watch product photo, stainless steel case, leather strap, dramatic studio lighting, black background, reflection, commercial photography
Pro (~6s, 2.5x cost)
"Luxury watch product photo, stainless steel case, leather st..."
Pro (~6s, 2.5x cost) result
Model: flux-2-pro
Luxury watch product photo, stainless steel case, leather strap, dramatic studio lighting, black background, reflection, commercial photography

Consider this: generating 100 images with Pro costs 2.5x more than Dev. If you're iterating on concepts or building a content library, Dev's excellent quality makes it the practical choice for volume work where budget matters.

Pro makes sense for final assets: the hero image on your homepage, the product shot for a print ad, the portfolio piece that represents your best work. A single image viewed thousands of times justifies the premium. But for exploration, iteration, and bulk content where "excellent" beats "good enough"? Dev is the economical choice that doesn't compromise on quality.

Note: A practical workflow: iterate with Dev until you find the right concept, then generate the final version with Pro for maximum polish.

Specifications

Feature Comparison

Technical specifications and capabilities for both models.

FeatureFlux 2 DevFlux 2 Pro
ReleaseJanuary 2025January 2025
ArchitectureFLUX.2 (open-weight)FLUX.2 (proprietary)
Image qualityExcellentPremium
Fine detailsVery GoodExcellent
Generation speed~2.5s~6s
Cost per imageBase cost~2.5x more expensive
Text renderingGoodBetter
Prompt adherenceExcellentExcellent
Image-to-image
ELO score~1143~1170
Try It Yourself

Try Flux 2 Dev

Try Flux 2 Dev with your own prompts. Generate images and compare results. Switch between Balanced (Flux 2 Dev) and High (Flux 2 Pro) quality routes.

Generated visual
https://demo.imagegpt.host/image?prompt=A+serene+Japanese+garden+with+a+red+maple+tree%2C+stone+lantern%2C+and+koi+pond%2C+morning+mist%2C+golden+hour+lighting&model=flux-2-dev

Frequently Asked Questions

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