EntityFieldsAnalyser (nuget): This Tool allow you to get an overview about your entity :  the Fields in your entity by Types. the percentage of use of each field in your entity. charting about: Managed/Unmanaged Fields in your Entity. The Count of Fields Per Type. the volume usage of your entity(about fields). You can Also display the data chart by percentage. The Count of Entities.  There's Also a field calculator to give you an idea if you can create such number of field of different types in your entity.
Keywords: XrmToolBox|Entity|Fields|Analyser|Calculator