Bat Speed and Bat Tracking, Explained: Inside Statcast's Swing Metrics

For two decades Statcast could tell you everything about a baseball after it left the bat — how hard, how high, how far — and almost nothing about the swing that sent it there. We were reading the consequence and guessing at the cause. A 115-mph exit velocity implied a violent swing, sure, but nobody was actually clocking the bat. That always struck me as a strange blind spot for a system this precise. In 2024 it closed. Statcast started tracking the barrel directly, and a swing that scouts had described for a century in adjectives — “quick hands,” “short to the ball,” “easy power” — finally had real numbers under it. Let’s unpack what those numbers measure, what counts as elite, and the trade-off they drag into the open.

Bat tracking is the hitting cousin of the metrics that already clock a runner’s legs and a catcher’s release: it measures the raw tool directly instead of inferring it from the result. And like those, the most interesting thing it taught us isn’t a leaderboard — it’s a tension, the one between swinging hard and actually hitting the ball.

Bat speed: how fast the barrel is moving

The headline metric is bat speed, reported in miles per hour. Statcast measures it at the sweet spot of the barrel — roughly six inches from the tip of the bat, the part that does the damage — at the moment of contact, or at the point of fastest movement through the swing on a miss. It is not the speed of the hands or the knob; it is the speed of the business end of the bat as it meets the ball.

Measuring at the sweet spot matters because a bat is a lever. The barrel travels far faster than the hands that drive it, and the tip faster still. By standardizing on the sweet-spot point, Statcast produces a number that is comparable from hitter to hitter and that lines up with where bat actually meets ball. A higher bat speed means more energy available to transfer into the baseball, which is the raw ingredient of exit velocity and power.

Crucially, bat speed is averaged only over a hitter’s competitive swings — the system filters out the soft, protect-the-plate checked swings and bunts that would drag the average down and tell you nothing about how hard a hitter can really go. The reported figure is meant to capture a hitter’s genuine swing, not his half-efforts with two strikes.

Swing length: how far the barrel travels

The companion metric is swing length, measured in feet. It is the total distance the barrel travels through space from the start of the swing to the point of contact — the length of the path the bat carves on its way to the ball. A long, looping swing covers more feet; a short, compact swing covers fewer.

Swing length is the natural counterweight to bat speed, because the two are linked by simple physics. A longer path gives the barrel more runway to accelerate, which tends to raise bat speed — but it also takes more time to complete, which means the hitter must commit earlier and has less margin to adjust to a pitch that moves or changes speed. A shorter swing sacrifices some of that built-up speed in exchange for quickness and adjustability. Reading bat speed and swing length together tells you how a hitter generates his speed: through a long, powerful path or a short, efficient one.

Fast-swing rate and squared-up rate

From those two core measurements, Statcast derives two rate stats that are often more useful than the raw averages, because they describe how often a hitter does something rather than his blended average.

Fast-swing rate is the share of a hitter’s competitive swings that clear a fixed bat-speed threshold — the cutoff Statcast uses to flag a genuinely fast swing. It answers a different question than average bat speed: not “how fast does he swing on average,” but “how often does he really let it rip?” A hitter who unloads on most swings will post a high fast-swing rate; a contact-first hitter who only sells out occasionally will post a low one even if his peak swings are quick.

Squared-up rate is the one I’d hand a newcomer first, because it measures contact quality from the other direction entirely. A swing is “squared up” when the hitter converts a high share of the available exit velocity — the most he could possibly have produced given his bat speed and the pitch speed — into actual exit velocity. In plain terms, it captures how flush the barrel met the ball, independent of how hard he swung. You can square up a ball with a gentle swing (a clean line drive on an off-speed pitch) and you can swing out of your shoes and badly mis-hit it. Squared-up rate isolates the flushness of contact from the violence of the swing — two things the old exit-velocity number jammed together.

That separation is the quiet payoff of bat tracking. Exit velocity is the product of two factors — how fast you swung and how cleanly you connected. Bat tracking pulls those apart: bat speed measures the effort, squared-up rate measures the precision, and exit velocity is what you get when you multiply them.

What counts as elite

As a well-established orientation, the league-average competitive bat speed sits in the low-70s of miles per hour, with the hardest swingers in the league pushing up toward and past 80. The honest read on any single figure is “elite,” “average,” or “slow” rather than over-trusting the decimal — the metric is young, the exact league average will drift as it matures, and the threshold is there to give a sense of scale, not a number to memorize. A hitter consistently near 80 mph has top-of-the-scale raw bat speed; one in the upper 60s is a contact-and-control hitter living off something other than barrel velocity.

The same care applies to the rate stats. A high fast-swing rate marks an all-out power hitter; a high squared-up rate marks a precise barrel regardless of swing effort. The most valuable hitters tend to pair a respectable bat speed with a high squared-up rate — they swing hard and hit it flush — but that combination is rare precisely because of the trade-off the metrics expose.

The central trade-off: speed versus contact

If you take one idea from this whole piece, take this one. The most important thing bat tracking exposed isn’t who swings fastest — it’s that swinging harder helps and hurts in the same motion. A faster bat carries more energy into the ball — more exit velocity, more power, longer fly balls — which is pure upside. But a faster, and especially a longer, swing is harder to control and harder to adjust mid-flight, which tends to cost contact: more swings and misses, more mis-hits, more strikeouts. Speed buys power and spends contact.

This is why average bat speed alone is a trap. The hitter with the fastest bat in the league is not automatically the best hitter; he may be trading away so much contact that the extra power never cashes in. And a hitter with a merely average bat speed can out-produce him by squaring the ball up far more often. The same logic runs through all of these tools: a capability is only worth what a player converts into results, and the conversion happens in the part the headline number can’t see. Bat speed is the engine; bat-to-ball skill is the steering. For how the resulting contact quality predicts power once the ball is struck, see our explainer on barrel rate, and for the broader family of directly-clocked tools, our overview of Statcast’s athleticism metrics.

How it’s measured

Bat tracking falls out of the same high-frame-rate optical tracking that powers the rest of modern Statcast. The system follows the bat through the swing and reconstructs the path and speed of the barrel’s sweet spot frame by frame, the same way it reconstructs the flight of the ball or the route of a fielder. Because it is derived from tracked positions rather than a sensor in the bat or a human estimate, the measurement is consistent from swing to swing and from hitter to hitter — the same leap in reliability that pop time made over the stopwatch. The competitive-swing filter then strips out the non-efforts so the averages reflect real swings.

The bottom line

Bat tracking finally put numbers on the swing itself. Bat speed clocks the barrel’s sweet spot in miles per hour; swing length measures the path it travels in feet; fast-swing rate counts how often a hitter truly unloads; and squared-up rate isolates how flush he meets the ball from how hard he swings. Read together, they pull exit velocity apart into effort and precision — and they expose the trade-off at the heart of hitting, where every mile per hour of bat speed buys power and quietly spends contact. Treat the thresholds as approximate landmarks on a young metric, not gospel. The fastest bat in the league is the start of the scouting report, not the verdict. What the hitter does with that speed — how often he squares it up — is what turns a violent swing into runs.