What Golf Club Shaft Flex Do I Need?

The shaft in your golf clubs is what connect your swing to the golf ball so playing the right shaft flex for your game is very important.

If you play the wrong golf shaft flex you could be adding unnecessary shots to your score.

Playing the wrong golf shaft flex can also lead to bad habits developing in your swing and golf game that are hard to shift.

Playing the right flex for your swing will help you match up your swing speed, tempo and club head with the ball. Confused? Let's dive into the magical world of golf shaft flex and see what we can do to help your game.

golf shaft flex overview chart

What Is Golf Shaft Flex?

Flex in a golf shaft determines the amount the shaft will bend during the swing and at impact. 

Pros or low handicap golfers, tend to use stiffer shafts. This is to adjust to the faster swing speeds and torque generated by stronger golfers to club head the best chance of being in the exact position it needs to be at the point of contact.

Players with slower swing speeds, such as seniors or lady golfers, will use a softer flex shaft to allow the clubhead to turn over naturally in the swing.

Depending on the manufacturer, shafts will fall into categories such as extra stiff, stiff, regular, ladies, or senior flex.

Golf Shaft Flex Letters

Have you ever seen the letters on a golf shaft and not understood what they mean. Here's a clear breakdown of what golf shaft letters mean;

  • SR = Soft Regular in America/Europe
  • R = Regular flex
  • SR = Stiff Regular in Asia
  • S = Stiff
  • S+ = Stiff Plus
  • X = Extra stiff
  • TX = Tour Extra stiff
  • L = Ladies flex
  • A = Senior flex
  • W = Wedge flex

Golf Club Shaft Flex Chart

This is a really useful golf shaft stiffness chart that matches up swing speeds to the appropriate flex. This is a good guide but as always, if in doubt, see a professional clubfitter for advice

Swing SpeedClubClubhead Speed RangeShaft Flex
Very FastDriver105 mph +X Stiff
3 Wood100 mph +X Stiff
3 Iron97 mph +X Stiff
6 Iron92 mph +X Stiff
FastDriver97-104 mphStiff
3 Wood93-97 mphStiff
3 Hybrid90-96 mphStiff
6 Iron84-91 mphStiff
AverageDriver84-96 mphRegular
3 Wood84-93 mphRegular
4 Hybrid80-90 mphRegular
6 Iron75-83 mphRegular
SlowDriver72-83 mphSenior
3 Wood70-80 mphSenior
4 Hybrid68-78 mphSenior
6 Iron65-75 mphSenior
LadiesDriver< 72 mphLadies
3 Wood< 70 mphLadies
4 Hybrid< 68 mphLadies
6 Iron< 65 mphLadies
shaft flex distance speed chart

How will golf shaft flex impact my game?

The flex of your golf club shaft has a big impact on the outcome of your game. Right through your golf bag, from driver, to irons to wedges, each golf club must have the correct shaft in order to optimize ball flight and trajectory.

Golfers with high swing speed are best suited using stiff shafts. This because when a soft shaft bends under high swing speed it "lags" behind where it should be and can't catch up with your hands. This can cause the club face to over-rotate at the bottom of the swing, causing a big hook.

On the other end of the scale, if you're a golfer with a slower swing speed using a stiff shaft, you will struggle to close the club face at impact, resulting in a dreaded slice.

correct flex shaft makes a difference

Shaft flex also has an impact on the height of your golf shots. For example, a faster swing speed golfer with a correctly fitted shaft flex will be able to hit a lower yet piercing ball flight. If they were using a regular flex shaft, it may cause the club face on all of their clubs to be de lofted at impact, resulting in a flight which is too low, combined with unpredictable distances.

What we want is to manage the spin rate of the ball which is generated relative to the swing speed of the golf swing. More speed can result in more spin, and more spin can result in a loss of distance as the ball balloons in the air. However spin is need to get the ball airborne, so slower swing speed golfers need a shaft which generates enough spin to help them out in this area.

As a general rule, you will use the same flex shafts in all of your clubs, with the exception of your wedges. Wedges tend to to have stiffer shafts, known as "wedge flex". They're not overly stiff, but they do encourage accuracy in these precision clubs.

You can judge the right flex shaft for you based on feel, and some people swear that in the hands of an amateur, flex doesn't matter. I think that shaft flex is an essential timing element in the golf swing, and to get this part of the game right, I'd always recommend seeking the help of a professional club fitter.

Shaft Flex by Golf Swing Speeds

Working out the correct shaft flex for you is usually done by working out your swing speed and then seeing which shaft flex is right for the club head speed you're generating. All of these speeds are with a driver.

  • Under 75 mph – Ladies flex  or Senior flex
  • 75 to 95 mph – Regular flex
  • 95 to 110 mph – Stiff flex
  • 110 mph and up – Stiff or Extra Stiff

This is a basic guide to follow.

Golf swing speed calculator

In order to work out your driver swing speed you can use these simple calculations.

Driver swing speed calculation option 1

Take your total carry distance with driver and divide it by 2.3.

Here are are two examples:

  • If your driver carried 240 yards.  Take 240 and divide it by 2.3.  Your approximate swing speed with the driver is 104 miles per hour.
  • If your driver carried 300 yards.  Take 300 and divide it by 2.3.  Your approximate swing speed with the driver is 130 miles per hour!

Driver swing speed calculation option 2

If you know your ball speed divide that number by 1.4.

What Do Golf Shaft Flex Numbers Mean

Golf shaft brands like Project X use numbers on their golf shafts instead of letter to describe the flex of the shaft. In this case the higher number on the golf shaft, the stiffer the shaft will be. Here are some examples;

Project X Golf Shaft Flex Chart

  • 7.0 - Tour extra stiff
  • 6.5 - Extra stiff
  • 6.0 - Stiff flex
  • 5.5 - Regular flex
  • 5.0 - Senior flex

Depending on the specific shaft, these numbers might shift slightly.

Signs you need a stiffer shaft

As you get better at the game of golf, our develop a more confident swing, you may begin to think that you need a stiffer shaft in your clubs. There are a few signs that this might be the case which are;

  • You're hooking the ball with all clubs
  • You can't control the distance of your irons consistently
  • The golf ball balloons in the air
  • You can't feel the club head in your swing

All of these can be signs that your shafts are too soft for your swing.

When to switch from stiff to regular shaft

I often find that too many players use stiff flex shafts. There is nothing wrong using a regular flex shaft and in truth shaft flex has no relation to skill level in golf. I have played with and had my ass kicked by plenty of seniors who are using super light and whippy shafts.

Here are some signs that it's time to switch from a stiff to a regular shaft;

  • You are hitting slices with your driver
  • You can't get the ball of the ground with woods and long irons
  • Ball flight is weak with mid and short irons
  • No spin on approach shots

These are some of the tell tale signs of a shaft which is too stiff for you.

What Shaft Flex Should I Use For My Driver

If you’re between 97 and 104 mph with the driver, you need a stiff flex.

If you’re between 84 and 96 mph, regular is going to be best for you. This is the swing speed rage of most amateur golfers.

Between 72 and 83 mph with the driver signifies you need to be hitting senior flex.

Swing speed for stiff shaft irons

IRON SHAFT HOW TO KNOW
6-iron Carry Distance6-iron Swing SpeedDriver Swing SpeedShaft flex (all clubs)
< 130 yards60 – 70 mph75 – 85 mphSenior Flex
131 – 155 yards71 – 80 mph86 – 95 mphRegular Flex
156 – 175 yards81 – 90 mph96 – 105 mphStiff Flex
> 176 yards91 + mph105 + mphX-Stiff Flex

7-iron swing speed chart shaft flex

7 iron distanceFull Swing3/4 SwingHalf Swing
<115LADY FLEXLADY FLEXSENIOR FLEX
115-130LEDY FLEXSENIOR FLEXSENIOR FLEX
130-145SENIOR FLEXREGULAR FLEXREGULAR FLEX
145-155REG FLEXREGULAR FLEXSTIFF FLEX
155-165STIFF FLEXSTIFF FLEXSTIFF FLEX
165-175STIFF FLEXX STIFF FLEXX STIFF FLEX
175+X STIFF FLEXX STIFF FLEXX STIFF FLEX
7 iron distance chart

Ping shaft flex chart

True Temper shaft chart

Dynamic Gold shaft chart

KBS shaft chart

kbs tour shaft chart
kbs shafts chart


Project X Shaft Flex Chart

Original Project X Rifle Irons

Tapered

  • Regular – 5.0
  • Regular Plus – 5.5
  • Stiff  – 6.0
  • Extra Stiff  – 6.5
  • Extra Stiff Plus – 7.0

Parallel

  • Regular Plus – 5.5
  • Stiff – 6.0
  • Extra Stiff – 6.5

Original Project X Woods & Hybrids

  • Regular Plus – 5.0
  • Stiff – 5.5
  • Stiff Plus – 6.0
  • Extra Stiff – 6.5
  • Extra Stiff Plus –7.0

Project X 95 Flighted Irons

  • Regular – 5.0
  • Regular Plus – 5.5
  • Stiff  – 6.0
  • Extra Stiff  – 6.5
  • Extra Stiff Plus – 7.0

PXi Irons

  • Regular – 5.0
  • Regular Plus – 5.5
  • Stiff Plus – 6.0 
  • Extra Stiff – 6.5

Rifle Irons

Parallel

  • Senior – 4.0
  • Regular – 5.0
  • Stiff – 6.0
  • Extra Stiff – 7.0

Tapered

  • Senior Plus – 4.5
  • Regular Plus – 5.5
  • Extra Stiff – 6.5

PX LZ Steel Irons

  • Regular – 5.0
  • Regular Plus – 5.5
  • Stiff – 6.0
  • Stiff Plus – 6.5

PX LZ Tour Graphite Irons

  • Regular – 5.0
  • Stiff – 6.0

PXv Tour Graphite Woods

  • Stiff – 5.5
  • Stiff Plus – 6.0
  • Extra Stiff Flex – 6.5
  • Extra Stiff Plus – 7.0

Project X Black Woods & Hybrids

  • Stiff – 5.5
  • Stiff Plus – 6.0
  • Extra Stiff – 6.5
  • Extra Stiff Plus – 7.0

HZRDUS Woods & Hybrids

  • Regular Plus – 5.5
  • Stiff – 6.0
  • Extra Stiff – 6.5

HZRDUS T1100 Woods

  • Regular Plus – 5.5
  • Stiff – 6.0
  • Extra Stiff – 6.5

EvenFlow Woods & Hybrids

(Available in Black and Blue)

  • Regular Plus – 5.5
  • Stiff – 6.0
  • Extra Stiff – 6.5
project x shaft flex chart

Conclusion

Using the correct shaft flex for your game is essential. You don't want to add shots because of your equipment and a poorly fitted shaft could be the cause of those wild hooks and slices. See a pro club fitter and get the right shaft for you. 

Last Updated on August 25, 2022 by Matt