# Pace Ladder > Pace Ladder (https://paceladder.app) is a free, browser-based running pace calculator. It converts between distance, finish time, pace (min/km and min/mi) and speed (km/h and mph), keeps all values in sync as the user types, and lists the finish times either side of the answer. It is aimed at runners setting goals from 5K to the marathon and at people converting treadmill speeds to pace. The site is free to use and will be funded by display advertising. Features: linked distance, time, pace and speed fields that update as the user types; a km/mi switch saved in the browser and in the URL (?units=mi); ± steppers, arrow-key and slider adjustment; a table of finish times around the target ("the ladder"); a reverse view listing finish times at 1K, 1 mile, 5K, 10K, 10 miles, half marathon, marathon, 50K and a custom distance for a given pace; even and negative splits per km or mile; a printable pace band; and estimated equivalent race times. The full calculator state is stored in a readable URL (for example https://paceladder.app/?half=1:20:00&units=mi), so a calculation can be shared as a link. Formulas: pace = time ÷ distance; min/km = 60 ÷ km/h; 1 mile = 1.609344 km; half marathon = 21.0975 km; marathon = 42.195 km. Paces are rounded to the nearest second. Equivalent race times are estimates from the Riegel formula, T2 = T1 × (D2/D1)^1.06. The formulas and rounding are documented at https://paceladder.app/how-we-calculate. Pages: one hub per distance (marathon, half marathon, 10 miles, 10K, 5K), one page per goal time at each distance (for example https://paceladder.app/half-marathon-pace/1-20), one page per pace in min/km and min/mi (for example https://paceladder.app/pace/3-30-per-km), converters for min/km to min/mi, km/h to pace and mph to pace, and a pace band generator. Results are rendered as plain HTML tables and are readable without JavaScript. ## Key facts - Email: hello@paceladder.app - Website: https://paceladder.app ## FAQ ### What pace do I need for a sub-3 marathon? To finish a marathon in under three hours you need to average faster than 4:16/km (6:52/mi), which is 14.1 km/h. ### How do I convert min/km to min/mile? Multiply the pace in min/km by 1.609344, so 5:00/km becomes 8:03/mi. ### How do I turn a treadmill speed into pace? Divide 60 by the speed: 12 km/h is 60 ÷ 12 = 5:00/km, and 6 mph is 10:00/mi. ### How long is a half marathon? A half marathon is 21.0975 km (13.1 miles), exactly half of the marathon’s 42.195 km. ### How accurate are the equivalent race times? They’re estimates from the Riegel formula and are only as good as your training for the other distance. ### What is a negative split? A negative split means running the second half of a race faster than the first. ### Can I share a calculation? Yes, the link holds the whole calculation, including km or miles, so whoever opens it sees the same numbers. ### Is Pace Ladder free? Yes, it’s free to use. Ads will pay for it, and they’ll never sit above the calculator. ## Pages - [Running pace calculator](https://paceladder.app/): Free running pace calculator. Change distance, time, pace or speed and the rest follow as you type, in km or miles, with the times either side of yours. - [Marathon pace](https://paceladder.app/marathon-pace): Marathon pace for any goal time in min/km, min/mi and km/h over the full 42.195 km, with splits, a printable pace band and the times either side of yours. - [Half marathon pace](https://paceladder.app/half-marathon-pace): Half marathon pace for any goal time in min/km, min/mi and km/h over 21.0975 km, with splits, a printable pace band and the times either side of yours. - [10 mile pace](https://paceladder.app/10-mile-pace): 10-mile race pace for any goal time in min/km, min/mi and km/h over 16.09 km, with splits, a printable pace band and the times either side of yours. - [10K pace](https://paceladder.app/10k-pace): 10K pace for any goal time in min/km, min/mi and km/h, with per-km and per-mile splits, a printable pace band and the 10K times either side of yours. - [5K pace](https://paceladder.app/5k-pace): 5K pace for any goal time in min/km, min/mi and km/h, with per-km and per-mile splits, a printable pace band and the 5K times either side of yours. - [How we calculate](https://paceladder.app/how-we-calculate): Formulas behind Pace Ladder: pace = time ÷ distance, exact race distances, pace rounded to the nearest second, and Riegel’s 1.06 exponent for estimates. - [min/km to min/mile](https://paceladder.app/min-per-km-to-min-per-mile): Convert pace from min/km to min/mile: multiply by 1.609344, so 5:00/km is 8:03/mi. Every common pace in one table, rounded to the nearest second. - [min/mile to min/km](https://paceladder.app/min-per-mile-to-min-per-km): Convert pace from min/mile to min/km: divide by 1.609344, so 8:00/mi is 4:58/km. Every common pace in one table, rounded to the nearest second. - [km/h to pace](https://paceladder.app/kmh-to-pace): Turn a treadmill speed into running pace: min/km = 60 ÷ km/h, so 12 km/h is 5:00/km and 8:03/mi. Table of common speeds, rounded to the nearest second. - [mph to pace](https://paceladder.app/mph-to-pace): Turn a treadmill speed in mph into running pace: min/mile = 60 ÷ mph, so 6 mph is 10:00/mi and 6:13/km. Table of common speeds, to the nearest second. - [Printable pace band](https://paceladder.app/pace-band): Make a printable pace band for your marathon, half, 10K or 5K: split times per km and per mile on a strip that fits your wrist. Prints in black and white.