Search entry → workshop
Swing Weight Calculator
Weigh the club, find the balance point, and read Lorythmic swingweight with a measurement range — then continue on the Club Bench.
423.0 g · BP 29.25" · 14" moment 6451 g·in
Estimated range: D6.7 – D9.4
How this swing weight calculator actually works
A finished golf club is a first-moment problem. Place the fulcrum fourteen inches from the butt. Multiply total mass by the distance from that fulcrum to the balance point. Convert that torque onto the Lorythmic alphabet (A0 through the Ds and beyond). That is the entire calculator. There is no hidden “head-feel” model and no launch-monitor guess.
Clubmakers have used this definition for decades because a dedicated swingweight scale is just a mechanical version of the same torque. If you own a gram scale and a way to mark the balance point, you can recover a number that is usually within a point of a lorythmic scale — provided you are honest about precision. A kitchen scale that jumps two grams, or a balance mark you only trust to a quarter inch, will fake a confidence the hardware does not have. That is why this page asks for scale ±g and balance ±inches and prints a range instead of a theatrical single letter.
Why searchers still want a simple calculator
Most people arriving here typed “swing weight calculator” because they have one club on a bench, not because they want a fourteen-club digital twin. So the tool stays three numbers. The Lab underneath is the same engine: the moment function is not rewritten for marketing pages. When you click Open in Club Builder Lab, the measured mass, balance, and length become a MEASURED club on the schematic, with the 14-inch fulcrum and CG markers already placed.
If you later add lead tape, shorten the shaft, or swap a 50 g grip for a 47 g grip, do that in the Lab’s what-if scenarios. Those changes are MODELLED. Keep the badges straight and you will not argue with a scale.
Practical measurement notes
Balance point is measured from the butt end of the grip, not from the end of the shaft under the cap. Playing length for woods and irons should follow the USGA/R&A 60-degree sole convention if you care about matching a length ruler; this calculator will not invent a posture for you. Putters use a different length axis and are outside the first-version focus.
Typical irons balance somewhere in the high 20-inch range from the butt; drivers sit farther out. If your balance point is near or behind the 14-inch fulcrum, the club is not behaving like a golf club and the letters will look absurd — that is the math warning you, not a bug.
FAQ
What inputs does a swing weight calculator need?
Total mass, balance point from the butt, and the 14-inch fulcrum convention. Playing length is stored for the bench but does not change the moment if mass and balance are known.
Why do you show a swingweight range?
Scale grams and balance eighths both move the 14-inch moment. Interval propagation turns those tolerances into a Lorythmic band such as D1.7–D2.4.
Is this Official scale or Lorythmic?
Lorythmic: 1.75 ounce-inches per point, D0 at 213.5 ounce-inches. That is the scale most clubmakers mean by D2.
Need the full bench? Open Club Builder Lab