Most of you (us) should stick with stiff.
But the stiff (S) and extra stiff (X) labels don’t answer the question on their own. No industry standard says what those letters actually measure, so one company's stiff can be firmer than another company's extra stiff.
That’s why we’re breaking down the difference between the two, so you can decide for yourself if you fall in the majority.
Table of Contents
- The Key Difference Between Stiff and Extra Stiff
- Who Should Play Stiff?
- Who Should Play Extra Stiff?
- How to Test Without a Launch Monitor
- What About Tour Extra Stiff?
- The Verdict
- Browse Stiff and Extra Stiff Shafts at Next Round Golf
The Key Difference Between Stiff and Extra Stiff
Stiff and extra stiff sound like a straightforward step up in resistance. In practice, the letters only tell part of the story. Here's what actually changes between the two, spec by spec: how much the shaft bends, how much it twists, and how fitters measure it.
Next Round Shaft Guide
Stiff vs. Extra Stiff: What Actually Changes
| Spec | What Changes S → XS | Watch For |
|---|---|---|
| Bend | Tip and butt sections both get stiffer; the shaft bends less under the same load and the bend profile shifts with it. | A shaft too stiff for you is one you can't load, however hard you swing. |
| Torque | Usually drops a touch moving from stiff to extra stiff, but not by a fixed amount or a predictable scale. | A stiff-flex shaft can still feel loose if its torque number runs high. See our golf shaft torque guide. |
| CPM | Extra stiff reads higher than stiff within a single model — but the number doesn't travel between models or brands. | Nippon Modus 120X (≈303 CPM) vs. 130X (≈336 CPM): same X label, same brand, 33-CPM gap that's entirely about weight, not flex (via GOLF.com). |
The letter is a starting point, not a spec. Some makers skip letters entirely — Project X's HZRDUS line runs on numeric codes like 6.0 and 6.5 instead.
Bend
An extra stiff shaft bends less than a stiff shaft under the same load. In the specs, tip and butt sections both get stiffer, torque usually drops a touch, and the bend profile shifts with it.
A shaft bends when you swing it. The head has weight, and weight resists being sped up, so the shaft bows back on the way down and springs toward straight through the strike. That is what golfers mean by loading a shaft.
A shaft too stiff for you is one you cannot bend much, however hard you swing.
Torque
Torque is its own measurement, separate from flex, and a stiff-flex shaft can still feel loose in your hands if its torque number runs high. Moving from stiff to extra stiff usually drops torque a touch too, but not by a fixed amount, and not on a scale you can predict from the letter alone. Don't equate "stiffer" with "better" until you've read up on torque specifically; our golf shaft torque guide is a good place to start.
CPM
CPM, cycles per minute, is the frequency reading fitters use to compare shafts. Within a single model, extra stiff reads higher than stiff, the same way it does on bend and torque. But the number doesn't travel well between models or brands, which is where CPM gets useful and confusing at once.
Tim Briand, Senior Vice President at True Spec Golf, works through an example on GOLF.com: a Nippon Modus 120X measures around 303 CPM, while a Modus 130X measures around 336. Both wear the same X label. Both come from the same company. The 33-CPM gap between them is entirely about weight, not flex.
Cross brands, the spread only widens. Some makers skip letters entirely; Project X's HZRDUS line runs on numeric codes like 6.0 and 6.5 instead.
Inconsistencies Within Brands
Finding a consistent difference between stiff and extra stiff is hard enough across brands. It turns out you can't count on it within a single brand either—the mismatch shows up even inside one manufacturer's own lineup. Fujikura's VENTUS TR spec page lists numeric tip-flex and butt-flex values for every shaft, every flex, though it never labels which direction the scale runs. Based on how the numbers step down from R to S to X within each model, lower appears to mean stiffer.
Read that way, the labels stop working. In the 6-weight class, the Blue+ in X flex reads tip 90, butt 76. The Black+ in S flex reads tip 87, butt 72, numerically stiffer in both sections, despite carrying the "lower" flex label. Same maker, same family, same weight class: the letters get it backwards.
Fujikura does publish real numbers for every flex: weight, torque, tip stiffness, butt stiffness. What it doesn't publish: a recommended swing speed, a CPM figure, or a definition of the Tour Extra Stiff (TX) flex it lists right there in the Blue+ table.
Bottom Line
The letters should act as a starting point, not a spec sheet. Bend, torque, and CPM all tell you something real, but only when you're comparing shaft to shaft, not label to label. The only way to know what a shaft actually does in your hands is to look at its numbers, or get fit.
Who Should Play Stiff?
Start with swing speed. Stiff converges around 95 to 105 mph of driver swing speed. You'll also find charts that start X at 110, but we recommend working from 105.
The profile that fits stiff:
-
Driver speed in the mid-90s to low 100s, consistently. Not your one best swing of the month.
-
Aggressive transition puts you toward the lower end of that range. Smooth, unhurried tempo puts you toward the top. Tempo loads a shaft as much as speed does, since a hard change of direction at the top puts more force into the shaft than a smooth one at the same speed, which is why two golfers at identical speed can legitimately need different flexes.
-
A flight that launches reasonably and a miss you can predict. Nothing here to fix.
X flex is generally for advanced golfers who already know the specs they need.
If you’re reading this and wondering if you should have moved up from a regular flex at all, check out the full regular vs stiff shaft breakdown.
Stiff shafts to look at
-
Aretera EC1 Blue driver shaft in stiff. This shaft is designed to load smoothly for higher-swing-speed players, without the boardy feel some stiff shafts give.
-
Fujikura VENTUS TR Velocore Blue driver shaft in stiff. The profile is ultra-stiff in the tip and stiff through the mid and handle. The stiffest part is the tip, where the ball is struck.
-
Graphite Design Tour AD XC fairway wood shaft in stiff. This is a low spin shaft with a mid-to-low flight, aimed at more carry and tighter dispersion.
Next Round Shaft Guide
Shop Stiff Shafts
Who Should Play Extra Stiff?
Extra stiff starts making sense above roughly 105 mph, with two qualifiers that are not on the chart.
First, focus on sustained speed rather than peak speed. True Spec puts it directly: if your first few swings read north of 105 and you then settle in around 100, extra stiff is probably not your shaft. It has to work for the swing you have on the 14th hole, not the one you had fresh on the range.
Second, look at your transition. An aggressive transition can push you toward X below 105, and a smooth one can keep you in stiff at 105.
Go too stiff and the symptoms come as a set. Launch drops and spin drops. Impact feels dead or harsh, because a shaft you cannot bend has little kick in it to feel. And the miss leaks right: pushes, fades, slices.
X is not something you grow into. If you like your ball flight and your results with a stiff shaft, moving up a flex is a move in the wrong direction.
Extra stiff shafts to look at
-
Fujikura VENTUS TR Velocore Black driver shaft in X. The low-launch, low-spin end of the family on Fujikura's own launch and spin ratings. On the same reading of the tip and butt numbers, it is firmer through the handle than the Blue.
-
Fujikura VENTUS TR Velocore Blue driver shaft in X. Same tip-stiff character as the stiff version, a step firmer for a swing that can load it.
-
Fujikura VENTUS TR Velocore Black fairway wood shaft in X. The fairway counterpart to that same low-launch, low-spin profile.
Next Round Shaft Guide
Shop Extra Stiff Shafts
How to Test Without a Launch Monitor
Three checks, in the order I would run them. Take all three before you decide.
Apex. Nick Heidelberger's published target on this site is a driver apex of around 100 feet.
Pick a tree line or a flagpole at roughly that height and watch where the ball peaks against it. A flight well under that 100 feet window, with pushes and slices, points at too stiff. A ballooning flight with a wide two-way cone, or a hard pull-hook, points at too soft.
In a Golfer Geeks driver test at Sterling Country Club, a +1 handicap swinging 118 mph hit a TaylorMade Qi10 Max in X-stiff and peaked at 101 feet, right around that target.
Apex goes first because it is the one launch number you can read by eye.
Miss direction. Watch where the bad ones go across a whole bucket, not one swing. Too stiff goes right. Too soft goes left. That's for a right-hander.
Read it alongside the apex check. Height and direction are halves of one pattern: the too-stiff flight comes with the too-stiff miss.
-
Push or fade, already in stiff: not an argument for X. Stiff is already at or past your limit, and X takes you further the way you're already missing.
-
Ballooning flight with a two-way miss: X is worth testing.
-
Dead pull that turns over hard: that's a regular-vs-stiff question, not a stiff-vs-X one.
-
Flight and miss pointing at different flexes: that's not telling you about flex at all. That's the case for getting measured.
Feel. Dead, harsh, boardy: that's a shaft too stiff for you to load. A shaft you can feel kick is one you're loading, because the kick is the shaft springing back, and a shaft that barely bends barely kicks.
Feel comes last because it's subjective. Two golfers can hit the same shaft and describe it differently.
You'll also hear that divot direction or shaft lean at impact can tell you whether your flex is right. Neither is among these three checks, and that's deliberate. I went looking for a source that ties either one to flex selection and couldn't find one, so I can't tell you how to read them.
Ignore them: focus on these three tests to determine your flex.
Next Round Shaft Guide
3 Tests to Check Your Flex
-
1
Apex
Watch peak height against a ~100' reference. Low + push/slice = too stiff. Ballooning + wide miss or hard pull-hook = too soft.
-
2
Miss Direction
Track misses across a whole bucket, not one swing. Too stiff goes right, too soft goes left (right-handers).
-
3
Feel
Dead, harsh, or boardy means a shaft too stiff to load. A shaft you can feel kick is one you're actually loading.
Skip divot direction and shaft lean. Neither has a reliable, sourced connection to flex selection — these three tests do the job.
What About Tour Extra Stiff?
Tour Extra Stiff, printed TX, sits above X.
On Fujikura's VENTUS TR table, TX is stiffer than X in both the tip and butt sections. Its torque is higher: 3.0 against 2.9 in the Blue+ 6, 2.8 against 2.7 in the Blue+ 7. So TX is not X with everything turned up; it’s a different bend profile, firmer overall but carrying slightly more torque.
Of Fujikura's three VENTUS TR models, only Blue+ offers TX at all. Black+ and Red+ stop at X.
If sustained speed well above 105 with a hard transition is not you, none of this changes your decision.
The Verdict
-
Stick with stiff. 95 to 105 mph, a normal flight, a miss you can plan around: the question is settled and there is nothing to buy. Spend the money on a lesson.
-
Test X. Consistently above 105 with an aggressive transition, or ballooning and spraying it out of your current stiff shaft. Same head, same ball, both flexes back to back, watching apex and dispersion rather than the one bomb.
-
Get measured. Your swing speed sits right on the line between stiff and X, and your misses go both left and right. A chart cannot see your transition, and the label does not say what the shaft measures. That is what a fitting with a launch monitor and CPM data settles.
Browse Stiff and Extra Stiff Shafts at Next Round Golf
Next Round stocks both flexes across the major shaft lines: the full stiff collection and the full extra stiff collection.
The ultimate golf shaft buying guide covers weight, torque and kick point, which is the layer underneath the flex letter. It says the same thing: use the speed chart to narrow your search, never to make the call.
