Sidespin
Sidespin is the sideways rotational component of a golf ball’s flight that causes the ball to curve left or right instead of flying straight. It happens when the clubface and swing path are misaligned at impact, which tilts the ball’s spin axis.
What is sidespin in golf?
Every golf shot carries two components of rotation: a vertical one and a horizontal one. Sidespin is the horizontal portion of that rotation. While backspin moves the ball through the vertical plane and helps it stay airborne, sidespin acts on the horizontal plane and pulls the ball off a straight line. Combined, these two forces dictate both the curvature and the overall flight of every shot a golfer hits.
In practice, a golf ball never spins on two separate axes at once. It spins on a single axis, and that axis can be perfectly vertical (pure backspin, dead straight flight) or tilted to one side. When the axis tilts, the ball curves. The amount of tilt is what most golfers and coaches still call “sidespin,” even though modern launch monitors measure it as spin axis tilt in degrees.
Sidespin matters. It is the mechanism behind every curving shot a golfer hits, the underlying reason that slices, hooks, draws, and fades all exist as variations of the same physical phenomenon. Just different magnitudes. Without any sidespin, every shot would fly arrow-straight, something even tour professionals rarely achieve.
How sidespin is created
A mismatch between the clubface angle and the swing path at the moment of impact is what creates sidespin. When the clubface points in a different direction than the club is travelling, the ball is squeezed against the face at an angle, which sets it spinning on a tilted axis.
For a right-handed golfer, an open clubface relative to the swing path tilts the axis to the right, producing a left-to-right sidespin and a shot that fades or slices. A closed clubface relative to the swing path tilts the axis to the left, producing right-to-left sidespin and a shot that draws or hooks. The greater the mismatch between face and path, the more the axis tilts, and the more dramatically the ball curves.
Strike location plays a role too. On modern drivers, contact toward the heel or toe creates “gear effect,” which spins the ball on a tilted axis even when the face and path are reasonably matched. A heel strike adds slice spin; a toe strike adds hook spin. This is why two swings that feel identical can produce wildly different shot shapes.
Sidespin vs. spin axis
This is where the terminology gets interesting. Many coaches and physicists, including the engineers behind Trackman, argue that “sidespin” does not technically exist as a separate force. The ball is not spinning sideways and backwards at the same time. It is spinning backwards on a tilted axis.
The two terms describe the same physical reality through different lenses:
| Term | What it describes | Common units | Where it’s used |
|---|---|---|---|
| Sidespin | The sideways component of spin that curves the ball | RPM | Casual instruction, older teaching, some launch monitors |
| Spin axis | The tilt angle of the ball’s single rotational axis relative to the horizon | Degrees | Trackman, Foresight, modern launch monitor analytics |
Trackman uses an airplane analogy to explain it: if a plane’s wings are parallel to the ground, it flies straight (a zero-degree spin axis). Tilt the wings left, the plane banks left; tilt them right, it banks right. The golf ball behaves the same way.
For a learning golfer, the two terms are functionally interchangeable. “Sidespin” remains the more intuitive way to describe what is happening to a slice or a hook. “Spin axis” is the precise term that launch monitor data will use.
Sidespin and the four curving shots
Every intentional or unintentional curve in golf comes from sidespin. The shape and severity of the curve depend on how much the spin axis is tilted, and in which direction.
| Shot shape (right-handed golfer) | Spin direction | Spin axis tilt | Typical curvature |
|---|---|---|---|
| Slice | Left-to-right | Large positive (10°+) | Severe right curve, often loss of distance |
| Fade | Left-to-right | Small positive (2-7°) | Gentle right curve, controlled |
| Draw | Right-to-left | Small negative (2-7°) | Gentle left curve, often added distance |
| Hook | Right-to-left | Large negative (10°+) | Severe left curve, hard to control |
According to Trackman’s published data, a shot carrying 150 yards with a 10-degree spin axis tilt will curve roughly 11 yards in the direction of the tilt. At 200 yards, the same tilt produces about 15 yards of curvature. The relationship is roughly linear, which is why curves get more punishing as shots get longer.
For left-handed golfers, the directions reverse. A positive spin axis still represents rightward curvature, but for a lefty, that rightward curve is a hook, not a slice.
Why pure backspin is rare
A shot with zero sidespin, or a zero-degree spin axis, is theoretically the ideal straight shot. In practice, it almost never happens. Tiny variations in clubface angle, swing path, and strike location mean that nearly every golf shot carries at least a small amount of axis tilt.
Trackman classifies a spin axis between roughly -2 and +2 degrees as a “straight” shot, since curvature in that range is barely visible to the eye. Even on the PGA Tour, average tee shots typically register some tilt. This is partly why professionals favour a repeatable shot shape, usually a small fade or small draw, over chasing an arrow-straight ball. A predictable curve is easier to play than a flight that could go either way.
Equipment also plays a role. Modern multi-layer urethane golf balls reduce the amount of spin imparted at impact compared to the wound balata balls of the 1990s, which is one reason today’s professionals appear to hit straighter shots than their predecessors.
Related Golf Terms
- Shaft — The long tube connecting the grip to the clubhead.
- Sidehill lie — When the ball is on a slope with the ball above or below the player’s feet.
- Shank — A mishit where the ball strikes the hosel of the club and shoots right.
- Setup — The overall position and alignment of the body before the swing.
- Short iron — Irons numbered 7-9 used for shorter approach shots.
Frequently Asked Questions
Is sidespin a real thing in golf?
Yes and no. The ball does curve sideways through the air, so the effect is real. But it spins on one tilted axis, not two. “Sidespin” is the practical name golfers and casual instruction tend to use, while “spin axis tilt” is the physically accurate term.
What is the difference between sidespin and backspin?
Backspin lifts the ball into the air and helps it stop on the green. Sidespin curves the ball left or right. Every shot has both. The mix between them determines the ball’s flight shape.
Does the golf ball affect sidespin?
Yes. Softer-cover urethane balls grip the clubface more and can produce more spin overall, including more sidespin. Firmer two-piece distance balls reduce spin in all directions, which is why they are often marketed as “straighter.”
Can sidespin be eliminated entirely?
Not realistically. Even tour-level swings produce some axis tilt on most shots. The goal for most golfers is to reduce sidespin enough to keep the ball in play, not to remove it completely.
Do launch monitors measure sidespin?
Yes, but most modern units (Trackman, Foresight) report it as spin axis tilt in degrees rather than as a separate RPM figure. SkyTrak and a handful of others still display sidespin in RPM for legacy reasons. Both numbers describe the same thing.
Sources
- Trackman. “What is Spin Axis?” Accessed May 2026.
- Rapsodo Golf. “Breaking Down Golf Ball Spin – Spin Rate vs Spin Axis.” Accessed May 2026.
- SkyTrak. “What Your Spin Numbers Are Actually Telling You.” Accessed May 2026.
- Performance Golf. “The Difference Between Draws and Fades in Golf Shots.” Accessed May 2026.
- Golficity. “Golf Ball Spin – Understanding the Basics of Backspin and Sidespin.” Accessed May 2026.
