For more years than I can remember the rule of thumb for when to re-string your racquet was never really adhered to for many reasons.

Years ago I constructed a simple formula to calculate the “String Frequency Recommended”.  This is now available to anyone by clicking on the “calculator” button on the “home” page of this site.

I have incorporated as much as I know about string and times played per year into the four (4) player categories.  So, you will not see these as separate fields.

String Density is approximately how much of the head area is filled with string.  I calculate this for every racquet but the values I have noted will be fine for your SFR input.

String Spacing M is the distance between main strings.  The more distance between strings the higher the number.  So, if the strings are .500 apart that would be input as “5”.  If the strings are .400 apart that would be input as “4”, and so on.

String Spacing X is the same as the above.

Using this calculator allows you can to play around with the variables to see which racquet properties will give you the longest string “viability”.  Strings loose tension well before they break and this calculator reflects that.  This calculator will maintain the best playability if adhered to.