DIALux evo vs Visual Interior Tool: Which Should You Use?
The verdict
DIALux evo and Visual Interior Tool are both home & construction design tools, compared here side by side. DIALux evo is free, with limits (Paid) and is a desktop install with no browser version; Visual Interior Tool is truly free (Free) and runs in any web browser with nothing to install. The biggest difference is cost: Visual Interior Tool is truly free, while DIALux evo is free, with limits (from Paid).
Free tiers & pricing last verified Jun 23, 2026.
Pick DIALux evo if…
Free, with limitsArchitectural and outdoor lighting engineers
Pick Visual Interior Tool if…
Truly freeQuick interior fixture-count estimates
Side by side
DIALux evo
Free, with limitsFull professional lighting calc/visualization is free forever; only luminaires from non-member manufacturers and IFC/BIM and Office export require the paid DIALux Pro subscription.
Visual Interior Tool
Truly freeCompletely free web lumen-method calculator for a rectangular room; gives average illuminance and fixture spacing only, not full point-by-point analysis.
Read the full reviews
DIALux evo
Full professional lighting calc/visualization is free forever; only luminaires from non-member manufacturers and IFC/BIM and Office export require the paid DIALux Pro subscription.
Visual Interior Tool
Completely free web lumen-method calculator for a rectangular room; gives average illuminance and fixture spacing only, not full point-by-point analysis.
DIALux evo vs Visual Interior Tool: questions, answered
What is the main difference between DIALux evo and Visual Interior Tool?
The biggest difference is cost: Visual Interior Tool is truly free, while DIALux evo is free, with limits (from Paid).
Is DIALux evo or Visual Interior Tool free?
DIALux evo is free, with limits and Visual Interior Tool is truly free. DIALux evo: Full professional lighting calc/visualization is free forever; only luminaires from non-member manufacturers and IFC/BIM and Office export require the paid DIALux Pro subscription. Visual Interior Tool: Completely free web lumen-method calculator for a rectangular room; gives average illuminance and fixture spacing only, not full point-by-point analysis.