Gut index

Gut is almost universally accepted as the best all-around playability string. So, in order to make lab numbers relate to the real world, we have indexed all properties of all strings to those of Babolat VS Power 16.

The resulting “gut index” shows each feature (stiffness for example) as a percentage of the same feature of Babolat VS Power 16. Babolat VS Power 16, of course, being 100%. Over 100% means that string has more of that property, less than 100% means it has less.

“More” and “less” does not mean “better” or “worse.” That depends on what a player likes in a string and it depends on the property.

Gut’s lab scores are at the “top” of every category except friction, where it is a lot less than most strings.

String Selector compares the gut index of your current string compared to all other strings based on your input on this screen.

So, every string is compared to your present string, and all strings are indexed relative to gut.