Flex, Speed
& Distance
Swing speed doesn't determine flex — timing does. But speed is what you can measure without a fitting. Here's how to use what you know to make better equipment decisions.
The Speed-Flex Myth
Most golfers believe flex is determined by swing speed. It's not — it's determined by when you release the club in the downswing. Two golfers with identical swing speeds can need completely different flex because their release timing differs. But swing speed is still the best starting point you have without a fitting — and getting it wrong based on speed alone is still better than not knowing at all.
The rule: If you don't know your release timing, use your swing speed as a starting point — but treat it as a range, not a fixed number. A 93mph golfer who thinks they need "stiff" is probably right about 40% of the time. The other 60% are playing the wrong flex.
Your Speed Zone
Where you fall tells you a lot — but not everything. Use this as a starting point, not a conclusion.
Under 90 mph
You likely lose distance from a shaft that's too heavy or too stiff. Lighter flex (L or A) with a mid-high launch profile typically adds 5-12 yards. Your transition is typically smooth with an earlier release — a shaft that loads earlier matches your pattern better.
90 - 105 mph
The broadest group. Most male recreational golfers with any athletic background sit here. Regular flex is the most common starting point — but transition timing is critical here. A 97mph golfer with a late release needs R-flex. A 97mph golfer with a early release might need S-flex. Don't guess based on speed alone.
105 - 115 mph
Better players, low handicappers, former athletes. S-flex is the typical starting point, but you may benefit from X-stiff in driver if your transition is very fast. At these speeds, equipment efficiency is high — wrong specs cost you more in yards than any other group.
115+ mph
Tour-level speed. X-flex or custom tour shafts are your range. At this speed, the shaft must be precisely matched — even small errors in flex or weight cause significant dispersion increases. If you're in this zone and not playing X-stiff, get fitted before your next equipment purchase.
How to Measure Your Swing Speed
Important: Your iron speed is typically 15-20% lower than your driver speed. If you only know one number, know your iron speed — it's more representative of your actual swing efficiency. Driver speed can be inflated by technique, course conditions, or luck. Iron speed is more consistent.
The Distance Formula
Speed matters, but it's not everything. Here's what actually determines how far your ball goes — and which variables you can control.
The takeaway: Shaft flex doesn't directly affect distance — it affects launch conditions, which affect distance. If your current flex is wrong, your launch angle and spin rate are suboptimal, and you're leaving yards on the table. Fix the flex, optimize the launch, gain the distance.