Estimate racket swingweight after adding mass, or solve for the mass or placement needed for a target using a 10 cm pivot.
Tennis Racket Swingweight Formula or Method
A point mass changes swingweight according to its mass and squared distance from the standard 10 cm butt pivot.
How the Calculation Works
The selected relationship is rearranged for the requested result. The requested output field is hidden, disabled, cleared, and made non-required so only the source inputs remain visible.
How to Use This Calculator
- Select the result you want in the Solve for menu.
- Enter only the visible source values from one consistent sample.
- Select Calculate and review the answer and substituted steps.
- Use Reset before starting a different sample.
Worked Example
Adding 4 g at 55 cm increases swingweight by 8.10 kg·cm², moving a 320 racket to about 328.10 kg·cm².
Input and Result Guide
| Item | How to use it |
|---|---|
| Base swingweight | Use a measured unmodified swingweight when possible. |
| Added mass | Enter the total mass added at the stated location. |
| Distance | Measure from the butt end to the added mass center. |
Interpreting the Result
Keep the sport, record scope, equipment setup, units, and source definitions consistent when comparing results.
Assumptions and Limitations
The point-mass model is an estimate. Distributed tape, manufacturing tolerance, handle additions, and measurement error require a swingweight machine for verification.
Common Questions
Why did an input disappear when I changed Solve for?
The hidden field is the requested output. Enter the remaining visible values and the calculator will solve for that target.
Will my last successful calculation be restored?
Yes. The calculator saves enabled source values and the successful result in this browser. Reset clears that saved state.
Sources
The standard parallel-axis point-mass approximation used in racket customization and swingweight measurement.