Cycling time estimator

Zero or negative average speed is rejected with a clear invalid_input error because division by a non-positive speed is not a ride plan.

What cycling riding time means and how it is computed

The closed formula is riding_time equals distance divided by average_speed, where distance and average_speed share the same unit system: forty kilometers at twenty kilometers per hour is two hours; twenty-five miles at twelve and a half miles per hour is also two hours. On success the response echoes rounded distance and average_speed, publishes riding_time_hours and riding_time_minutes with fixed twelve-decimal rounding, sets riding_time_formatted to a compact human string such as two hours thirty minutes, and includes formula and steps so worksheets and automated tests can assert every intermediate line.

How to call the API and what comes back

Send a JSON body with two required finite numbers: distance (aliases dist, d, length, total_distance, ride_distance) and average_speed (aliases speed, avg_speed, v, velocity, ride_speed). Distance must be strictly positive and at most one million; average_speed must be strictly positive and at most ten thousand per hour so intermediate quotients stay finite in IEEE double precision on the Worker and in the browser. On success the response echoes rounded distance and average_speed, sets riding_time_hours to distance divided by average_speed, riding_time_minutes to that value times sixty, riding_time_formatted to a compact hour-and-minute label built from whole minutes after rounding, formula to the string riding_time equals distance divided by average_speed, message to a short English summary, and steps to an ordered array of substitution lines. Failed validation—missing fields, non-finite numbers, values outside published limits, zero or negative distance, zero or negative average_speed, or a non-finite quotient—returns invalid_input and is never charged. Pricing is a flat $0.002 per successful request with unit item and zero marginal unit price. Prefer numeric JSON fields when you control the client; string numbers are accepted only when they match a strict finite numeric pattern without units or trailing text.

Practical tips, limits, and related searches

Typical recreational averages fall between twelve and twenty-five kilometers per hour; trained road groups often sit higher, and e-bike assist can push averages further—still well under the catalog maximum. Prefer this capability when you already know distance and a planned or historical average speed and only need pure riding duration; if your source is a GPS track, extract distance and moving average first. Keep distance and average_speed inside the published ranges so the quotient cannot overflow into a non-finite riding time that the solver must reject. When teaching or testing, pair examples: forty kilometers at twenty kilometers per hour yields two hours and a clean two-hour formatted string; thirty kilometers at fifteen kilometers per hour yields two hours as well; ninety minutes of seat time can be recovered from forty-five kilometers at thirty kilometers per hour; and average_speed equal to zero demonstrates the hard invalid_input path that protects against divide-by-zero. This landing targets people searching for a cycling time estimator, bike ride duration, or average speed distance calculator for bicycles; it is not a road-trip car ETA tool, not a multi-stop itinerary planner, and not a calorie or power model. Failed tasks that return invalid_input do not consume prepaid balance, which keeps exploratory scripts cheap when you deliberately probe the zero-speed error. Round-trip checks are easy: recompute distance divided by average_speed by hand and confirm it equals riding_time_hours within the same twelve-decimal rounding, and confirm that riding_time_minutes equals that value times sixty after the same rounding policy.