TennisTension Pro description

An active subscription plan (chose one from the app settings) is required to read the measurement results, save and keep them in the history section. Billing is recurring and you can cancel anytime.

TennisTension Pro is the best working mobile app for both Android and IOS devices that instantly measures the current string tension of a tennis racket string with an accuracy of 0.1kg. The app records and analyzes the ringing sound heard from the strings when hit with a stiff object (key, pen, pencil, another racket, fingernails, etc.).

TennisTension Pro and its predecessor TennisTension have been flawlessly used by more than 3000 professionals, amateur players and stringers since February 2019. We have been testing and improving the app performance in cooperation with several certified stringers and professional players with ATP and WTA rankings.

Three new features are included since April 2023:

Choose a specific string model from a string library with more than 100 world's most popular string models.
Saving different racket/string configurations in a library.
Saving the measurement results in a History section for tracking the Tension Loss.


If you define correctly all racket and string parameters the measurement accuracy is proved to be approximately 0.1kg (0.2lbs).

TennisTension Pro is capable to calculate the average string tension between mains and crosses. If a racket is strung 24/23kg, then the measurement result will be approximately 23.5kg.

Sometimes, especially when the app is used for the first time, the user struggles to produce good enough "ringing" sound from the string.

Remove any anti-vibration devices!

Knock lightly the string several times anywhere on the stringbed with any stiff (preferably light) object such as key, pen, pencil, fingernails, another racket, etc. Keep the ringing string close (2 to 10cm) and in front of the microphone (situated at the bottom of the phone). In about a second the result will be shown.
Do not touch the vibrating string after it is knocked with anything (e.g fingers) during the measurement!

Hybrid strings can also be measured.

A user can be surprised by the results of lower tension than expected because of the "Tension Loss" negligence. The Tension Loss can be up to 6kg(13lbs) when the string is very old. Usually, string tension drops 1,5kg in the first 24 hours after stringing and 3kg or more after a week.

A "Calibration" can be used for obtaining measurement results with even better accuracy.

By regularly using TennisTension Pro, every tennis player can improve his all on-court performance by better choosing the right string and racquet configuration, the optimal string tension depending on the different playing conditions, tracking the Tension Loss for every string model used and last but not least, control and adjust faster to the way different stringers string at various sites and tournaments.