Golf Shaft Flex Chart: Swing Speed to Flex

Published golf shaft flex charts agree on the order of the flexes but not on where one ends and the next begins. A speed near a boundary can be regular on one chart and regular-or-stiff on another. This page puts two charts side by side, shows where they split, and explains how to use the overlap to choose flexes to test.

What shaft flex means

Flex is how much a shaft bends under load during the swing. A softer shaft bends more and a stiffer one bends less, which changes how the head arrives at the ball. Shafts are labelled with letters, usually L (ladies), A or senior, R (regular), S (stiff) and X (extra stiff). Charts match those labels to driver swing speed in miles per hour, because swing speed is the easiest number for a buyer to get.

The catch is that the labels are not a measurement. GolfLink puts it bluntly: there is no industry standard in shaft flex (GolfLink, stiff vs regular shaft). Next Round Golf says the same in different words: A Stiff shaft in one model can feel and perform differently from a Stiff shaft in another. (Next Round Golf flex chart).

Two flex charts side by side

These are the driver swing speed ranges each source publishes, in mph, copied as written. Neither is a manufacturer's own spec for a particular shaft. They are retailer and publisher guides, and neither states how its cutoffs were derived, so treat them as two opinions about the same question.

Next Round Golf also lists a soft regular and a tour extra stiff, but gives no speed for either. It points readers to the shaft's own fitting guidance for soft regular and says tour extra stiff is model-specific, so fitting is recommended.

Where the two charts disagree

• Overlapping ranges versus clean steps. GolfLink's ranges overlap: senior runs 70-84 and regular starts at 80, and regular ends at 94 while stiff starts at 90. Next Round Golf's ranges meet end to end.
• The regular start. GolfLink starts regular at 80; Next Round Golf starts it at about 85.
• The stiff range. GolfLink's stiff runs 90-109. Next Round Golf's runs about 95–105, a much narrower band.
• Ladies. GolfLink says up to 75; Next Round Golf says under 70.
• Extra stiff. Both charts start extra stiff at 105, but GolfLink keeps stiff valid to 109. Next Round Golf also notes that PGA TOUR Superstore puts stiff at 95–110 and extra stiff above 110. Cutoffs vary even between one retailer's own pages, so any single table is a rough guide.

Quick lookup (both charts combined; where they differ, both flexes are named):

• Under 70: ladies on both.
• 70 up to 80: senior on both; GolfLink also lists ladies up to 75.
• 80 up to 85: senior on both; GolfLink also lists regular.
• 85 up to 90: regular on both; Next Round Golf also lists senior at 85.
• 90 up to 95: regular on both; GolfLink also lists stiff.
• 95 up to 105: stiff on both; Next Round Golf also lists regular at 95.
• 105 up to 110: extra stiff on both; GolfLink also lists stiff.
• 110 and up: extra stiff on both.

Why the cutoffs differ

Two separate things are going on. First, both charts are editorial rules of thumb with no stated method, so nothing forces their cutoffs to match. GolfLink's overlap reflects that it is loose about boundaries. Second, flex labels are not standardised across shaft models: GolfLink says every manufacturer uses its own scale to determine which shafts are regular or stiff, so one brand's stiff can be another's regular. Swing speed alone also misses tempo and strike quality. GolfLink notes that If you have a quicker tempo that puts more load on the shaft, a stiffer shaft could be a better option.

How to use a chart without over-trusting it

1. Get a real driver speed. Use a launch monitor, a fitting bay or a radar unit, and average your normal swings, not your best. If you only have a distance estimate, our golf swing speed chart and driver distance calculator shows how speed and distance relate, but it is a distance tool, not a flex recommendation.
2. Find your speed in more than one chart. Note every flex that claims it. If a single flex is named by every chart, start there. If two are named, you have your pair to test.
3. Check the exact shaft's own guide. A model's maker publishes its own flex guidance, and that outranks any general chart. Ask which flex of that specific model suits your speed.
4. Hit both neighbouring flexes. Change only the flex: keep the same head and similar shaft length and weight. GolfLink says a shaft that is too stiff leads to a lower ball flight, loss of distance and a push tendency. A shaft with too much flex becomes whippy, and GolfLink says the miss then goes left and right. Compare dispersion and strike feel, ideally with a fitter. If you cannot test both, one fitter quoted by GolfLink says If you're right on the fence, I would highly and always recommend going with the weaker flex. Treat that as one opinion; a quicker tempo is GolfLink's reason to move stiffer.

Driver, irons and the rest of the bag

The charts above are driver charts; both are about driver swing speed. Neither source gives iron-shaft cutoffs, so this page has none; ask a fitter or the shaft maker about irons. Shaft length is a separate spec that also changes how a club plays, so tell a fitter about it too.

What these charts do not tell you

They do not predict distance, and this page makes no distance claim. They do not account for shaft weight, torque or bend profile, which is why a stiff in one model can feel different from a stiff in another. For the ratio between swing speed and distance, see the swing speed page linked above. For how every club in the bag fits together, start from the full club distance chart.