Roll-Time Putting V19

Roll-Time • Distance Control • Player Development

Developed by John King Golf

Experience Essential training tools

Roll-Time Calculator

Estimate time to the cup and time until the ball stops. Select green speed, slope, and desired finishing distance.

15 ft
10.0 ft
24 inches
—Estimated Time to Cup
—Estimated Time to Stop
—Effective Stimp (Equivalent)
—Estimated Entry Speed at Hole (mph)
Putting Performance Details
—Initial Speed (ft/s)
—Modeled Deceleration (ft/s²)
—Predicted Total Roll Distance (ft)
—Effective Hole Diameter
Illustrative reference: At 1.68 mph, an effective hole diameter of approximately 3.1 inches has been cited in putting research. This is not a validated prediction for all conditions. Other speeds require a validated lookup curve; no extrapolation is performed.
Preliminary constant-deceleration model checked against a measured Stimp 10, 15 ft, 2.5% uphill putt: 3.00 seconds to hole, stopping 24 inches past. Calculations are estimates, not validated predictions for every green, slope, or speed.

Measure Entry Speed At The Hole

The stopwatch measures travel time, not instantaneous ball speed. To estimate entry speed, mark two points a short, known distance apart, centered on the hole (for example 6 inches before and 6 inches after). Time the ball crossing those two marks using video, then divide distance by elapsed time.

Important: This is average speed across the segment, an approximation of speed at the hole. A shorter segment improves locality but needs high-frame-rate video for reliable timing. Do not use this method if the ball drops into the hole; use a flat target marker instead.

—Estimated Speed at Hole (mph)
Record a video, use the frame controls to identify when the ball crosses each mark, and enter the elapsed time here, or use the two Entry Speed video markers in Stopwatch to fill this measurement automatically. If your measurement equipment provides a directly measured entry speed, use that value instead.

Field Calibration &Amp; Validation

Verified benchmark: Stimp 10 ft · 15 ft to hole · 2.5% uphill · 3.00 s to hole · 24 in past hole (17 ft total). This benchmark is retained and is not overwritten by new tests.

Calculating benchmark…

Add A Measured Putt

Additional measurements are saved on this device and compared with the model. They do not automatically change the formula.

Start Here

Learn how roll time relates to distance control, then use the Calculator, Stopwatch, Metronome, and Challenges to practice. Advanced measurements are available in Coach Mode.

Learn Roll-Time Putting

A practical guide to predicting ball roll, training distance control, reading greens, and using Roll-Time Putting tools.

Select any topic below to expand it. You can open multiple topics at once.

The Roll-Time Concept

Putting is a relationship between distance, speed, and time. Roll time is the elapsed time from putter impact until the ball reaches a selected point (such as the hole) or comes to rest. These are two different measurements: time to the cup and time to stop.

On a fast green, a ball generally needs less initial speed to cover the same distance than on a slower green. Uphill, downhill, and sidehill slopes also affect the required speed, travel time, and break. There is no single correct time for every 10- or 20-foot putt.

Roll-Time Putting adds a measurable reference to traditional feel. The objective is to recognize and reproduce a useful roll-time pattern under comparable conditions.

Distance Control & Speed Awareness

Choose a distance and a desired finishing position. Predict how long the ball should take to reach the hole, then putt and compare your prediction with the measured result.

  1. Set the hole distance and assess green speed and slope.
  2. Choose a finishing-speed intention, such as stopping at the hole or rolling 12–24 inches past.
  3. Use the calculator for an estimated reference time.
  4. Visualize the ball's pace, make the stroke, and observe its finishing distance.
  5. Measure the time and repeat to reduce variation.

Coaching key: judge time and finishing distance together. Matching a time is not success if the ball finishes in the wrong place.

Green Reading & Break

Line and speed must be read together. A faster putt may require a different starting line than a slower putt on the same slope. As the ball slows, gravity has more time to influence its path, so break can become more noticeable late in the roll.

Identify the slope, choose an intended arrival speed, picture where the ball begins to curve, and select a starting line that matches that speed. Practice the same putt at different speeds to see how the path changes.

Sidehill training: watch both the ball's travel time and the amount of break. A roll-time target alone cannot determine the correct aiming line.

Putt Visualization & Pre-Shot Routine

Train your eyes and imagination to predict the entire roll—not just the starting direction.

  1. Read: assess slope, surface speed, and break.
  2. Choose: select the intended finishing speed and stopping point.
  3. See: picture the ball starting on line, slowing, breaking, and approaching the hole.
  4. Sense: anticipate the approximate travel time.
  5. Execute: let the stroke respond naturally to that picture.
  6. Evaluate: compare the actual roll with the intended speed, line, and finish.

As skill improves, this becomes a quick on-course routine rather than a lengthy calculation.

Training Progression

Baseline: On a fairly level green, hit 10 putts from 10 or 15 feet. Record roll time and where each ball stops.

Time awareness: Before each putt, predict its time to the cup. Compare prediction, measured time, and finish.

Variable distances: Move between short, medium, and long putts. Learn how appropriate roll speed and duration change.

Slope & break: Add uphill, downhill, and sidehill putts. Adjust both speed intention and starting line.

Transfer: On the course, use the visual routine without relying on a timer for every putt. Measure selectively during practice to check progress.

Using The App's Training Tools

Roll-Time Calculator: Estimate time to the cup and time to stop from distance, green speed, slope, and intended roll past the hole. Treat outputs as estimates to calibrate with real putts.

Target Roll Duration: Practice predicting and reproducing a target time.

Stopwatch: Time a putt manually, with sound-triggered start, or using a countdown. Manual reaction time and environmental noise can affect measurements.

Video Frame Marking: Select or record a video, then mark impact and the destination/stop frame. Timing precision depends on frame rate and marker accuracy.

Metronome: Train stroke rhythm using adjustable beats per minute and the displayed time between beats. Stroke tempo is not the same measurement as ball-roll duration.

Challenges & Results: Test consistency, save practice outcomes, and review trends.

Putting Data: Review available measurements such as ball speed, distance, skid, and roll percentage alongside intended stopping distance. Keep imported measurements distinct from stopwatch times unless shots are reliably matched.

How To Measure Improvement

Evaluate several related outcomes rather than a single number: finishing-distance error, time consistency on comparable putts, accuracy of time predictions, short/long tendencies, and line/speed coordination on breaking putts.

For meaningful comparisons, record the intended hole distance, desired roll past the hole, slope, and green conditions. A putt finishing past the cup may be exactly what you intended; score it against the chosen stopping target, not automatically against the hole.

Look for tighter patterns across repeated sessions and better decisions on the course—not merely a faster or slower roll.

The JKG Roll-Time Putting Philosophy

See the Roll. Feel the Speed. Trust the Stroke.

Measurement helps players understand the relationship between speed, time, distance, and slope. Visualization turns that information into a clear intention. Repetition helps transform the intention into instinctive performance.

Measure → Understand → Visualize → Execute → Evaluate → Repeat.

The purpose is not to replace feel with numbers. It is to use numbers to develop better feel.

Target Roll Duration

Develop distance control using slope, break, and a target time. The distance and green speed are shared with the Calculator.

25 ftPutting Distance
Stimp 10Green Speed
Level putt • 0% slope • Straight break.
—Estimated Roll Time With Selected Slope
—Distance for 5 seconds
Simplified straight-line model using Stimp calibration (6.4 ft/s launch speed) and gravity along the selected slope. Break direction is descriptive only; it does not calculate curved ball travel or cross-slope. Steep downhill slopes may not allow a ball to stop in this model. Grass, grain, skid and real green conditions vary; calibrate using measured putts.
—Time Difference (Seconds)
—Absolute Roll-Time Error (%)
The target slider calculates a stopping distance for the chosen roll duration and longitudinal slope. Sidehill percentage describes cross-slope; break direction is descriptive only and does not predict curved travel. These are model estimates, not measured green behavior.

Smart Roll-Time Measurement

Partner taps Start at impact and Stop when ball stops.

Tap Start at impact and Stop when the ball comes to rest. Manual reaction time adds measurement error.

0.00

Putting Tempo Metronome

Train a consistent putting rhythm with an audible beep on every beat. Set the tempo in beats per minute (BPM) and see the exact time between beats.

Time Between Beats
0.789 s
Current Tempo
76 BPM
BEAT
—
Ready

Tap Start to enable audio. Each beat sounds once; adjusting BPM while playing updates the rhythm.

Training tip: one beep can mark the start of the backswing and the next a repeatable rhythm reference. For a two-beat stroke, the time between those reference points is 60 ÷ BPM seconds. Use device volume to adjust loudness.

Putting Challenges

Predict the roll duration, putt toward the target, time the actual roll, and record how far the ball finished from the target.

JKG Putting Data Analysis

Import individual putts, compare distance control with your intended target, and save player sessions on this device. Your imported measurements are preserved on this device.

Use a CSV file containing individual putts. Column names such as Total, Ball Speed, Launch Direction, Side, Skid Distance, Roll Percentage, Roll Speed, Speed Drop, and Effective Stimp are recognized. PDF reports and screenshots cannot be imported automatically.

Paste CSV Data / Manual Entry

For manual entry, use one Total distance per line, or paste a full table with column headings. Check the units in your source file; Total distances are interpreted as feet unless labeled otherwise.

Ready to import putting data.

Session Performance

0Putts
—Average Total Distance
—Average Error vs Stopping Target
—Average Absolute Error
—Distance Range
—Within Tolerance
—Short / Long / On Target
—Average Roll Percentage
Import shot data to see coaching observations.

Individual Putts

#Total (ft)Error (ft)Ball SpeedLaunch DirectionSideSkidRoll %Roll SpeedSpeed DropEffective Stimp

Saved Putting Sessions

Sessions are stored in this browser on this device. Export JSON for backup before clearing browser data or switching devices.

Player Results

0Challenges completed
—Finished within 3 feet
—Average leave (ft)
—Average timing error (sec)
DatePlayerTargetTimeLeaveConditions

Settings

Player and Coach Experiences

Player: Learn, calculate, measure, practice, and review results without advanced analysis menus.

Coach: All Player tools plus Entry Speed & Calibration, Putting Data Analysis, detailed calculator metrics, and video entry-speed markers.

Use the Player / Coach switch above the menu to change modes. Your choice is saved on this device. Switching modes never deletes your results.

Coach Mode is an interface preference, not a password-protected account. Results are stored locally on this device unless you export them.

John King Golf — Contact &Amp; Coaching

John King, PGA

(334) 759-0013

johnking@pga.com

johnkinggolf.com

Book Coaching — MyPGA Schedule

Install On Your Device

Host this app over HTTPS, open it in Safari on iPhone/iPad, then use Share → Add to Home Screen → Open as Web App. On supported desktop browsers, use the browser's Install option.

Privacy And Storage

Player names and results are saved only in this browser's local storage. They are not synced across devices. Export backups regularly; clearing browser data can erase records. Avoid entering sensitive player information.

Version 17 • Roll-Time Putting • Offline-ready after first successful hosted load.