Smash Factor with your putter? Yes, we call it Impact Ratio

September 21, 2019

Smash Factor, the ratio between club speed and ball speed, is a key data point when it comes to locking in your driving game. It’s also a key data point in the putting world, but since “smash” is the last thing you want to hear while grooving a smooth, reliable stroke, we call it Impact Ratio.

Impact Ratio affects your ability to sink putts because different putter models often produce drastically different values. Face inserts, grooves, materials and weight combine to generate a wide range of ball speeds, even off the same stroke speed. Knowing this, you might consider a putter with a lower Impact Ratio if you play on fast greens. The opposite is also true, but you can change the ratio, too, depending on your technique.


The more you accelerate your putter through impact, the more you increase the force, generating a higher Impact Ratio. Now you know why distance control is so maddening: It demands that you replicate the exact same rate of acceleration (and, therefore, Impact Ratio) on every stroke. Difficult!

Where you typically make contact on the face also affects Impact Ratio: the farther the strike point from the sweet spot, the lower — and more unpredictable — the ball speed. Long strokes also produce lower ratios, because timing the strike is more difficult than with a short stroke. Talk to a putter-fitter.

With a little help, you can optimize Impact Ratio for both your chosen putter and your stroke. That’s an impact with lasting, positive effects.

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