ReluxDesktop – Professional lighting
and sensor planning

Standard-compliant planning and simulation of artificial light, daylight and sensors in real time.
For beginners and professionals in lighting design. Intuitive operation and simple and fast display
of the calculation values.

NEW in update 2024.1 Real-time renderer for impressive visualisations!

Download and use now free of charge

What does the software offer?

ReluxDesktop is a powerful and intuitive application for the simulation of artificial light and daylight.

ReluxDesktop allows you to plan individual rooms, entire floors, industrial halls or outdoor areas such as car parks, sports facilities and roads – all in just one piece of software.

Calculation of absolute values, national and international standards, compatible with CAD and BIM systems. ReluxDesktop supports the import and export of different formats. You can also plan sensors using ReluxDesktop – the only software on the market that allows you to do so. ReluxDesktop makes the planning of emergency lighting particularly easy and accurate.

Quick and easy calculation of lighting values in less than 2 minutes using ReluxExpress.

The programme can be extended to meet the users’ needs through add-ons and plug-ins.

Import / export numerous formats: Import (ies, ldt, ROLF, gbXML, ReCad, 3ds, dxf, dwg, xlsx, PDF, geolocations from GoogleMaps), Export (dwg, ReCad,, xlsx)

Interface to BIM: A bidirectional interface to Revit enables loss-free communication with the ReluxDesktop lighting design programme and the ReluxCAD for Revit Add-on.

The software is free of charge. Why?

ReluxDesktop can be downloaded free of charge and used for personal, educational and commercial purposes. Thanks to the support of industry partners, the software is available free of charge.

A large number of luminaires and sensors are provided by RELUX members free of charge for planning purposes. Luminaires from non-Relux members are displayed anonymously and can be displayed by purchasing a ThirdParty licence.

Impressive renderings
with real-time renderer in ReluxDesktop
Create photorealistic visualisations and revolutionise lighting planning.
Real-time renderer in ReluxDesktop powered by Enscape®

Use the real-time renderer to visualise and present your projects. Change and move objects in ReluxDesktop
and assess the effect in real time. With the 3D objects from the ReluxNet database you can make your project even more realistic.
The real-time renderer can be used free of charge in the latest ReluxDesktop version.
Download Page
to Realtime-Renderer
How does the
realtime renderer work?
Simple activation and use of the real-time renderer in ReluxDesktop.
Use examples to see how you can use the renderer and what is possible.
For example, the simulation of times of day and cloud density.
Simulations of light and sensors
in real time in 2D and 3D
Simple visualisation of the light calculation
and display of false colours
Light calculation for indoor
and outdoor sports fields
Which standards are supported?
Indoor area
EN 12464-1:2021
EN 12464-1:2011
EN 12193:2018
EN 1838:2014
ASR A3.4:2011
CIE 97:2005
TS 22012:2019
CIE 117:1995
US best practice
Outdoor area
EN 12464-2:2014
EN 12193:2018
EN 13201-2:2015
DIN 67523-2:2010
SLG 202:2006
CIE 112:1994
US best practice
EN 13201-2:2015
Training and further education offering

Relux supports lighting designers with a wide range of training and further education courses – from beginner to professional.

  • Free tutorials
  • Live courses online and on-site
  • Certified tutors
  • Company-specific training courses
  • Training courses in German, English, Italian, French, Spanish and Dutch
What sets ReluxDesktop apart?
Validated calculation results
CIE Test Report [PDF]
Free tutorials
and YouTube videos
Extensive luminaire and
sensor database
Free support
and knowledge base
International (26 languages)
Trusted company
since 1998
Regular updates
and extensions
Professional lighting design in just a few steps
1. Room creation and room allocation

Select your environment or room and define its mass and shape. Use CAD drawings, gbXML or Geolocations to create the scene. Or import the room using the Metaroom app.

Creating rooms
2. Selecting luminaires and sensors

ReluxNet provides you with over 1 million items for your planning, including luminaires, sensors and 3D objects. You can easily add the files to your ReluxDesktop project with one click.

Over 1 million products
(luminaires and sensors) on ReluxNet
3. Placement and visualisation of the results

You can place the selected luminaires and sensors in the room or have them placed automatically and add windows, doors, objects and measuring surfaces to the room. You assign the desired luminaire type for the basic lighting.

When the lighting simulation is started, the room is calculated correctly in terms of lighting technology.

A luminaire list provides clarity regarding which luminaires have been placed where in the room. The photometric results can be checked in the 2D and 3D views and then output as tables or false colours.

Lighting design with measurement surfaces
and various view options in 2D and 3D
Lighting calculations using Relux
Representation of
light distribution curve in ReluxDesktop

Stargard Science Center Filary, Poland

Lichtplaner: Maciej Lewandowski
Visualisation /
rendering in ReluxDesktop

Stargardzkie Centrum Nauki Filary, Poland

Lighting Designer: Maciej Lewandowski
Retail space


Lighting Designer: Maurizio Ciavolella, Studionit


Lighting Designer: Maurizio Ciavolella, Studionit
Use free of charge now


to Realtime-Renderer

Customer feedback
ReluxDesktop with the Add-on ReluxCAD for Revit improves the work flow for lighting design using Revit. A great tool for both lighting designers and electrical engineers.

Kristina Allison
Senior Lighting Designer, Atkins London, United Kingdom
I have been using Relux for over 10 years. Relux allows me to carry out complex lighting calculations in different areas. Relux is particularly suitable for sports lighting. Due to its high speed and user-friendly interface, Relux is one of the best programs for lighting calculations.

Ivan Verevkin
Lighting Designer, Wolta, Georgia
I can plan a standard-compliant outdoor lighting installation quickly and efficiently using Relux Desktop. Thanks to the individual setting options of the user interface, I also have all the important information and tools at hand at all times.

Andreas Kellermann
Outdoor Lighting Designer, Trilux, Germany
I use ReluxDesktop as the #1 tool because the standard-compliant planning and mapping of daylight and artificial light are possible. I also greatly appreciate the innovative interfaces to different formats. This allows me to work on my projects much more efficiently and achieves a significantly higher order probability. I can recommend it without reservation.

Matté Hilpert
DIN-certified lighting technician, Trilux, Sonepar Deutschland GmbH