Clocked: Speed Estimator

Clocked estimates the speed of vehicles, bikes and people crossing your camera's view: cars, trucks, buses, motorcycles, bicycles, runners and walkers, plus larger animals such as dogs. Hold your phone steady and side-on to a road or path, and it shows an estimated speed with a ± range. How it works 1. Detect and track: an object-detection model runs on your phone, finds targets in each camera frame and follows the moving one nearest the middle. Tap another box to switch. 2. Pixels to directions: the camera's lens data turns each point in the picture into a direction, and the motion sensors give its tilt for every frame. 3. Scale: in Auto, the lens height above the road and the point where the wheels or feet touch the ground give the target's distance. In Known distance, you measure it. 4. Fit: positions across many frames, each with the camera's own timestamp, are fitted to a line. Distance per second is the estimated speed. Three ways to measure, all free • Auto: Clocked learns the lens height from the cars and people that pass, using their typical size. Until one has passed it asks for one, and it marks a reading "~" until a second agrees. Or set it by hand. • Known distance: type the measured distance to the path, and Clocked turns the target's angle into its position along it. Passes toward or away from you are refused. • Stopwatch: tap as a target passes two marks a known distance apart. Plain timing, no camera. Two-mark calibration, also free: aim at two marks at measured distances and Clocked solves the lens height and the camera's tilt together, narrowing the ± range. Accuracy and limitations Every reading is an estimate. The ± is a live uncertainty estimate from the track's fit, the tilt sensor, the lens height or distance, and the lens data: a model, not a guaranteed error limit. Works best when: • the phone is braced on a post, wall or fence • the target crosses side-on, about 10 to 30 m (30 to 100 ft) away • the ground is flat and the wheels or feet are in view • the lens height is learned, set or calibrated, or the distance is measured Works poorly when: • the target heads toward or away from you • the phone shakes, pans or tilts • the target is far away, small, partly hidden or poorly lit • the road slopes or the ground is uneven • an unusual size (a small animal, a tall truck) misleads the automatic lens height When it detects a problem, Clocked says so instead of showing a confident number: "Hold steady", "Level the phone", "Too far", "Coming toward you: low accuracy" or "No reading: sizes don't match the lens height". An estimate, not a precision instrument Clocked is not a certified or calibrated measuring device. Its readings are estimates for curiosity, sport and informal traffic surveys, and must not be used for legal, enforcement or safety-critical purposes, or to make claims about anyone's driving. Clocked Pro, an optional in-app upgrade • Zoom lock-on: 2x or 3x for passes further away, with the math following the zoom. • Analyse: your logged passes with median, 85th percentile, a histogram, time of day and filters, plus CSV export. • Speed alert: a tone and a red badge when a reading passes your own limit. • Box colors and styles. • Snapshot: a photo stamped with the estimated speed and ±. Every firm reading is logged on your phone, free or Pro, and Analyse, snapshots and zoom each have a short daily preview. Also free: km/h or mph, landscape or portrait, full-screen or framed view, a low-power mode and two app icons. Stay safe Stand somewhere safe and watch your surroundings. Never step into traffic to place a mark or take a reading, and never use Clocked while driving or cycling. Privacy No ads. No accounts. No subscriptions. Camera frames are processed on your phone to estimate speed. Your settings and pass log are kept on your phone. We receive anonymous usage stats. Clocked is a Zone7 Studios app: https://clocked.zone7studios.com