What is the ideal bench press bar path?

A clean bar path is a slight J-curve: the bar touches the lower chest or upper abdomen and moves up-and-back over the shoulders at lockout. A perfectly vertical path forces the shoulders to do too much work and is a common cause of pec strain.

How wide should my elbows flare on bench press?

Most lifters do best with 45-75 degrees of elbow flare relative to the torso. Tucked tighter than 45° turns the bench into a triceps-dominant lift and limits chest growth; flared past 75° puts the shoulder in an unstable, injury-prone position.

Why is my bench press uneven at lockout?

Uneven lockout (one arm finishes before the other) is usually a strength imbalance between the two sides of the chest or a wrist alignment issue. Form Detective flags it via per-side 3D wrist tracking, and unilateral DB pressing typically resolves it within 6-8 weeks.

Should I arch my back when I bench press?

A natural lumbar arch with your butt staying on the bench is fine and actually safer for the shoulders. The aggressive arches you see in powerlifting meets are a sport-specific technique and not required for hypertrophy benching.

What camera angle is best for bench press?

Side-on, level with the bar, captures bar path and elbow angle clearly. Place the phone 2-3 meters away, perpendicular to the bench, at bar height when the bar is racked.

Free AI Bench Press Form Check — Bar Path, Elbow Flare & Lockout

The bench press errors Form Detective detects

Every error is detected from a 3D skeleton reconstructed from your video — not just one camera angle.

Bar path drift

The bar's trajectory from chest to lockout is plotted in 3D so you can see whether it drifts toward your face or away.

Elbow flare

The angle between your upper arm and torso is measured at the bottom of every rep — flared elbows are flagged with severity.

Uneven lockout

Left vs right elbow extension at the top is compared frame-by-frame, catching the side that lags or shifts.

Shoulder position

Scapular protraction and shoulder elevation are tracked so you can spot reps where you lose the upper back arch.

Tempo & sticking points

Per-rep timing reveals where the bar slows or stalls — usually a few inches off the chest under heavy weight.

Wrist position

Wrist extension is tracked so you can fix the "broken wrist" position that leaks force on heavy presses.

How the analysis works

Form Detective runs YOLO pose detection, refines the keypoints with ViTPose, and reconstructs a true 3D skeleton with VideoPose3D. Bench-specific thresholds turn that into rep-by-rep written feedback plus a scrubbable 3D replay. Read the full pipeline overview →

What you get back

Per-rep score and a clear list of which reps had which issues
3D skeleton replay you can scrub and rotate
Bar path overlay rep by rep
A personalized warmup & cooldown routine for shoulders, pecs and triceps that adapts to your recurring issues
An AI coach chat that remembers your past bench sessions

How to film a good bench video

Camera positioned at chest height, 1.5–2 meters out, slightly off-center (avoid pure side or pure foot view)
Make sure the bar and both elbows are in frame for the entire rep
One working set per upload is ideal

Frequently asked questions

Will it catch elbow flare on heavy singles?

Yes. Elbow angle is measured on every rep regardless of load — that's the point of rep-by-rep analysis.

Does it analyze close-grip and incline bench?

Bench press analysis is tuned for the flat barbell bench press. Close-grip works well; incline is detected and analyzed but with slightly fewer error types.

How much does it cost?

Free for daily use. Heavier usage is covered by a one-time credit pack — no subscription required.

Also check your other lifts

Squat form check · Deadlift form check · How the 3D analysis works · Lifting form blog