The software

Fast and powerful modeling

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We would like to get your feedback on the current version of RefFIT so that we can improve the different functions and capabilities of the software. Let us know what you like and what you don’t like by filling in this questionnaire: Questionnaire | Reffit

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If you encounter any problems registering, logging in or downloading the software, do not hesitate to contact us: reffit at

When you use RefFIT for your data analysis, please indicate this in your published work by citing:

“Kramers-Kronig constrained variational analysis of optical data”,  A. B. Kuzmenko, Review of Scientific Instruments 76, 083108 (2005).