Molecular Weight Calculator - .NET DLL Version

.NET DLL version of the Molecular Weight Calculator, supporting a range of molecular weight calculations for both chemical formulas and amino acids.


The MwtWinDll.NET program contains utility functions for calculating the molecular weight and percent composition of chemical formulas and amino acids. It recognizes user-definable abbreviations and custom elemental isotopes. It also includes a Mole/Mass Converter, Formula Finder, Capillary Flow Modeller, Amino Acid Notation Converter, Isotopic Distribution Calculator, and Peptide Sequence Fragmentation Modeler. Although the DLL is a VB.NET application, it is C# compatible.

To use the MwtWinDll.NET program you need to include it in a .NET project. The Peptide Fragmentation Modeller program is a simple VB.NET command-line application that demonstrates the use of the MwtWinDll.NET program. Also available for download is a simple C# demo application that demonstrates the use of MwtWinDll.dll with C sharp.

See also the desktop version of the Molecular Weight Calculator (which is written in VB6).



All publications that utilize this software should provide appropriate acknowledgement to PNNL and the Molecular-Weight-Calculator-DLL GitHub repository. However, if the software is extended or modified, then any subsequent publications should include a more extensive statement, as shown in the Readme file for the given application or on the website that more fully describes the application.


These programs are primarily designed to run on Windows machines. Please use them at your own risk. This material was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the United States Department of Energy, nor Battelle, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness or any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.

Portions of this research were supported by the NIH National Center for Research Resources (Grant RR018522), the W.R. Wiley Environmental Molecular Science Laboratory (a national scientific user facility sponsored by the U.S. Department of Energy’s Office of Biological and Environmental Research and located at PNNL), and the National Institute of Allergy and Infectious Diseases (NIH/DHHS through interagency agreement Y1-AI-4894-01). PNNL is operated by Battelle Memorial Institute for the U.S. Department of Energy under contract DE-AC05-76RL0 1830.

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