Available for online use here:
https://rodrigocfd.github.io/string-tension-calc
- Compares string tension of multiple guitars at once;
 - Calculates tension in kg/cm, lb/in or Newton;
 - Plots a line chart comparing the tensions;
 - Supports 6, 7 and 8 string guitars;
 - Supports multi-scale guitars (fanned frets);
 - Provides several pre-configured commercial string packs;
 - Allows customization of string packs;
 - Provides several pre-configured tunings;
 - Allows customization of tunings.
 
Unit weights taken from D'Addario catalog.
Licensed under MIT license, see LICENSE.md for details.