.IES File Extension

IES Photometric Data File

Developer Illuminating Engineering Society
2.9  |  14 Votes

What is a IES file?

An IES file is a plain text file that contains measurements of light and light quantities. It is saved in a format specified by the Illuminating Engineering Society (IES). Building designers and civil engineers use IES files to simulate lighting systems while designing buildings, roadways, parks, and other structures.

More Information

Screenshot of a .ies file in Apple TextEdit
IES file open in Apple TextEdit

Lighting manufacturers commonly create and publish IES files that designers and engineers can use to model how a lighting system behaves. These files describe how a lighting installation's light moves throughout a room or other area.

Many architectural programs that can simulate lighting, such as Autodesk Revit, allow engineers and designers to load IES files and use them in their models. Some interior design and 3D art programs also support IES files.

How to open a IES file

You can use an IES file to simulate a light source in 3D modeling tools like Autodesk Revit LT (Windows), Autodesk AutoCAD (Windows, Mac), and Acuity Brands Lighting Visual Lighting (Windows).

To view the lighting information an IES file contains in an organized format, open the file in IESviewer (Windows), jSolutions Inc. Photometrics Pro (Windows), or Acuity Brands Lighting Visual Photometric Tool (Web). You can also open an IES file in any text editor, such as Microsoft Notepad or Apple TextEdit, to quickly view the plain text data it contains.

How to convert a IES file

You can use the PhotoView module included in OxyTech LITESTAR 4D Open to convert IES files to the following formats:

  • .LDT - Eulumdat Formatted Luminaire Data
  • .LTL - Luminaire Data
  • CIE - International Commission on Illumination Data

You can use the online Eulumdat Tools IES to ELUMDAT Converter to convert IES files to the LDT format.

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Programs that open IES files

Verified by FileInfo.com

The FileInfo.com team has independently researched the IES Photometric Data file format and Mac and Windows apps listed on this page. Our goal is 100% accuracy and we only publish information about file types that we have verified.

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