Flux Fill Pro
Black Forest Labs' mask-based inpainting model. Pixel-perfect localized edits — paint a mask over the region you want changed, describe what should fill it, the rest of the image is untouched. The complement to Flux Kontext: Kontext for instruction-based whole-image edits, Fill Pro for precision regional work.
At a glance
- Price
- 5 Credits
- Our rating
What Flux Fill Pro is best for
How Flux Fill Pro performs
Strengths
- precision inpainting with mask control
- preserves untouched regions perfectly
- fast
Limitations
- requires mask input — not pure instruction-following
- less suited for text-only edit prompts
How to prompt Flux Fill Pro
Practical tips to get the most out of Flux Fill Pro.
- 01draw masks precisely — sloppy masks produce sloppy results
- 02describe what should fill the masked region
- 03use for localized edits, not full image transformations
Tips are tuned for Flux Fill Pro specifically.
Made with Flux Fill Pro
Alternatives to Flux Fill Pro
Other models on Upsampler that cover similar ground.
Nano Banana 2 (with masking)
Google DeepMind's Gemini 3-powered flagship for text-to-image. Renders up to 4K with industry-leading prompt adherence, native multi-image references, and web search grounding for factual scenes. Ideal for product photography with brand consistency, character series across multi-shot campaigns, and complex compositional work that benefits from compositing several references at once.
Flux Kontext Pro
Black Forest Labs' instruction-based image editor — describe an edit in plain English ('replace the background with a sunset beach', 'change the shirt to red') and get a clean result that preserves the rest of the scene. Strong identity and lighting consistency makes it production-ready for outfit swaps, background replacement, and prop changes.
Frequently asked questions
What is Flux Fill Pro?
Black Forest Labs' mask-based inpainting model. Pixel-perfect localized edits — paint a mask over the region you want changed, describe what should fill it, the rest of the image is untouched. The complement to Flux Kontext: Kontext for instruction-based whole-image edits, Fill Pro for precision regional work.
How much does Flux Fill Pro cost on Upsampler?
5 credits per generation. No subscription, credits never expire.
What are alternatives to Flux Fill Pro?
Common alternatives: Nano Banana 2 (with masking), Flux Kontext Pro.
Can I try Flux Fill Pro for free?
You can try a free, no-signup version of our ai image editor. Note that the free version may use a different, lighter model rather than Flux Fill Pro itself.