{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"hiking-time"},"result":{"entity_type":"calculator","id":"hiking-time","calculator_id":"hiking-time","canonical_url":"https://tttkmbb.com/fitness/hiking-time","name":"Hiking Time Calculator","title":"Hiking Time Calculator – Naismith's Rule, Langmuir Corrections and Tobler's Hiking Function","category":"fitness","category_name":"Sports & Fitness","tool_name":"estimate_hiking_time","featured_mcp_tool":false,"description":"Estimates the time for a hike from distance, ascent and descent with Naismith's rule (1 h per 5 km plus 1 h per 600 m of ascent), Naismith with Langmuir's descent corrections, or Tobler's hiking function (speed = 6·e^(−3.5·|slope + 0.05|) km/h), with a pace factor for slower parties and optional breaks; all three estimates are reported.","use_when":"You need a planning time for a walk or mountain hike from map distance and elevation gain/loss, or want to compare the Naismith and Tobler estimates.","do_not_use_when":"You need running pace or race predictions (use running-pace or race-time-predictor), the route involves scrambling, snow, heavy loads or trackless terrain (the rules assume walkable paths), or you have a full elevation profile (segment-wise Tobler is more accurate than the whole-route net gradient used here).","inputs":[{"name":"distance_km","label":"Distance","type":"number","unit":"km","required":true,"max":500,"exclusive_min":0,"description":"Horizontal (map) distance of the route in kilometres.","example":10},{"name":"ascent_m","label":"Total ascent","type":"number","unit":"m","required":false,"default":0,"min":0,"max":20000,"description":"Cumulative elevation gain in metres.","example":500},{"name":"descent_m","label":"Total descent","type":"number","unit":"m","required":false,"default":0,"min":0,"max":20000,"description":"Cumulative elevation loss in metres (used by the Langmuir corrections and by Tobler's net slope).","example":0},{"name":"method","label":"Method","type":"enum","required":false,"default":"naismith","values":[{"value":"naismith","label":"Naismith's rule (5 km/h + 1 h per 600 m of ascent)"},{"value":"naismith_langmuir","label":"Naismith's rule with Langmuir's descent corrections","aliases":["langmuir"]},{"value":"tobler","label":"Tobler's hiking function"}],"description":"Rule used for the primary time; the other estimates are still reported.","example":"naismith"},{"name":"descent_steep","label":"Steep descent (> 12°)","type":"boolean","required":false,"default":false,"description":"Langmuir only: true when the descent is on slopes steeper than 12° (adds 10 min per 300 m of descent); false treats it as a gentle 5–12° descent (subtracts 10 min per 300 m).","example":false},{"name":"pace_factor","label":"Pace factor","type":"number","required":false,"default":1,"min":0.5,"max":3,"description":"Multiplier on the moving time: 1.0 = fit walker (Naismith's 5 km/h), 1.25 = slower or laden group (Langmuir's 4 km/h), 1.5 = family with children.","example":1},{"name":"break_minutes_per_hour","label":"Breaks per hour","type":"number","unit":"min/h","required":false,"default":0,"min":0,"max":30,"description":"Rest time added per hour of moving time.","example":0}],"outputs":[{"name":"time_hours","label":"Total time","type":"number","unit":"h","decimals":2,"description":"Moving time by the chosen method plus breaks."},{"name":"time_text","label":"Total time (text)","type":"string","decimals":4,"description":"Total time as hours and minutes, e.g. '2 h 50 min'."},{"name":"moving_time_hours","label":"Moving time","type":"number","unit":"h","decimals":2,"description":"Time by the chosen method with pace_factor applied, without breaks."},{"name":"average_speed_km_h","label":"Average speed","type":"number","unit":"km/h","decimals":2,"description":"distance_km / time_hours (breaks included)."},{"name":"ascent_time_minutes","label":"Ascent allowance","type":"number","unit":"min","decimals":1,"description":"Naismith's ascent allowance: 1 minute per 10 m of ascent, × pace_factor."},{"name":"naismith_time_hours","label":"Naismith time","type":"number","unit":"h","decimals":2,"description":"Naismith's rule moving time × pace_factor, always reported."},{"name":"naismith_langmuir_time_hours","label":"Naismith-Langmuir time","type":"number","unit":"h","decimals":2,"description":"Naismith's rule with Langmuir's descent correction, × pace_factor, always reported."},{"name":"tobler_time_hours","label":"Tobler time","type":"number","unit":"h","decimals":2,"description":"distance_km / Tobler speed at the route's net slope (ascent − descent) / distance, × pace_factor, always reported."},{"name":"tobler_speed_km_h","label":"Tobler speed","type":"number","unit":"km/h","decimals":2,"description":"6·e^(−3.5·|slope + 0.05|) at the net slope; 5.04 km/h on the flat, 6 km/h maximum at a −5 % descent."}],"input_schema":{"type":"object","properties":{"distance_km":{"description":"Horizontal (map) distance of the route in kilometres. Unit: km.","type":"number","maximum":500,"exclusiveMinimum":0,"examples":[10],"x-unit":"km"},"ascent_m":{"description":"Cumulative elevation gain in metres. Unit: m.","type":"number","minimum":0,"maximum":20000,"default":0,"examples":[500],"x-unit":"m"},"descent_m":{"description":"Cumulative elevation loss in metres (used by the Langmuir corrections and by Tobler's net slope). Unit: m.","type":"number","minimum":0,"maximum":20000,"default":0,"examples":[0],"x-unit":"m"},"method":{"description":"Rule used for the primary time; the other estimates are still reported.","type":"string","enum":["naismith","naismith_langmuir","tobler"],"default":"naismith","examples":["naismith"]},"descent_steep":{"description":"Langmuir only: true when the descent is on slopes steeper than 12° (adds 10 min per 300 m of descent); false treats it as a gentle 5–12° descent (subtracts 10 min per 300 m).","type":"boolean","default":false,"examples":[false]},"pace_factor":{"description":"Multiplier on the moving time: 1.0 = fit walker (Naismith's 5 km/h), 1.25 = slower or laden group (Langmuir's 4 km/h), 1.5 = family with children.","type":"number","minimum":0.5,"maximum":3,"default":1,"examples":[1]},"break_minutes_per_hour":{"description":"Rest time added per hour of moving time. Unit: min/h.","type":"number","minimum":0,"maximum":30,"default":0,"examples":[0],"x-unit":"min/h"}},"additionalProperties":false,"required":["distance_km"]},"output_schema":{"type":"object","properties":{"time_hours":{"description":"Moving time by the chosen method plus breaks. Unit: h.","type":"number","x-unit":"h"},"time_text":{"description":"Total time as hours and minutes, e.g. '2 h 50 min'.","type":"string"},"moving_time_hours":{"description":"Time by the chosen method with pace_factor applied, without breaks. Unit: h.","type":"number","x-unit":"h"},"average_speed_km_h":{"description":"distance_km / time_hours (breaks included). Unit: km/h.","type":"number","x-unit":"km/h"},"ascent_time_minutes":{"description":"Naismith's ascent allowance: 1 minute per 10 m of ascent, × pace_factor. Unit: min.","type":"number","x-unit":"min"},"naismith_time_hours":{"description":"Naismith's rule moving time × pace_factor, always reported. Unit: h.","type":"number","x-unit":"h"},"naismith_langmuir_time_hours":{"description":"Naismith's rule with Langmuir's descent correction, × pace_factor, always reported. Unit: h.","type":"number","x-unit":"h"},"tobler_time_hours":{"description":"distance_km / Tobler speed at the route's net slope (ascent − descent) / distance, × pace_factor, always reported. Unit: h.","type":"number","x-unit":"h"},"tobler_speed_km_h":{"description":"6·e^(−3.5·|slope + 0.05|) at the net slope; 5.04 km/h on the flat, 6 km/h maximum at a −5 % descent. Unit: km/h.","type":"number","x-unit":"km/h"}}},"formula":"Naismith: t = distance_km / 5 + ascent_m / 600 (hours). Langmuir: t = Naismith − descent_m / 300 × 10 min (gentle 5–12° descent) or + descent_m / 300 × 10 min (descent steeper than 12°). Tobler: v = 6 · e^(−3.5 · |(ascent_m − descent_m) / (1000 · distance_km) + 0.05|) km/h, t = distance_km / v. moving_time_hours = t × pace_factor; time_hours = moving_time_hours × (1 + break_minutes_per_hour / 60)","method":"Naismith's rule (1892) and Langmuir's corrections (1984) are planning heuristics for fit walkers on paths; Tobler's function (1993) is an exponential fit to Imhof's walking data with a maximum of 6 km/h on a slight −5 % downhill. Applying Tobler to a whole route uses the net gradient, so a route with equal ascent and descent is treated as flat and its time is underestimated; descents on slopes below 5° get no Langmuir correction and should be left out of descent_m.","sources":[{"name":"Wikipedia – Naismith's rule (with Langmuir's corrections)","url":"https://en.wikipedia.org/wiki/Naismith%27s_rule","type":"reference","retrieved_at":"2026-09-24"},{"name":"Wikipedia – Tobler's hiking function","url":"https://en.wikipedia.org/wiki/Tobler%27s_hiking_function","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"10 km with 500 m ascent, Naismith","inputs":{"distance_km":10,"ascent_m":500,"method":"naismith"},"expected":{"time_hours":2.83,"time_text":"2 h 50 min","moving_time_hours":2.83,"average_speed_km_h":3.53,"ascent_time_minutes":50,"naismith_time_hours":2.83,"tobler_time_hours":2.37,"tobler_speed_km_h":4.23},"url":"https://tttkmbb.com/api/v1/calculate/hiking-time?distance_km=10&ascent_m=500&method=naismith"},{"name":"12 km, 800 m up and down, Langmuir, 10 min breaks per hour","inputs":{"distance_km":12,"ascent_m":800,"descent_m":800,"method":"naismith_langmuir","break_minutes_per_hour":10},"expected":{"moving_time_hours":3.29,"time_hours":3.84,"time_text":"3 h 50 min","naismith_time_hours":3.73,"naismith_langmuir_time_hours":3.29,"tobler_time_hours":2.38,"tobler_speed_km_h":5.04},"url":"https://tttkmbb.com/api/v1/calculate/hiking-time?distance_km=12&ascent_m=800&descent_m=800&method=naismith_langmuir&break_minutes_per_hour=10"}],"faq":[{"q":"Which method should I use?","a":"Naismith for a first estimate on trails; add Langmuir's corrections when the route has long descents; Tobler when the gradient is fairly uniform (here it sees only the net gradient of the whole route)."},{"q":"Is distance_km the map distance or the GPS track length?","a":"The horizontal map distance, which is what all three rules expect; a 3D track length is slightly longer on steep ground and would over-estimate the time."},{"q":"How do I allow for a slower group?","a":"pace_factor scales the moving time: 1.25 corresponds to Langmuir's 4 km/h base speed for less fit or heavily laden parties; breaks are added separately with break_minutes_per_hour."}],"tags":["hiking time","naismith's rule","tobler hiking function","langmuir correction","trail time estimate","walking time"],"related":[{"calculator_id":"calories-burned","reason":"Energy cost of the hike (MET 6.0 for cross-country hiking)."},{"calculator_id":"steps-to-distance","reason":"Convert a step count into hiking distance."},{"calculator_id":"running-pace","reason":"Pace and splits for running the same distance."}],"links":{"html":"https://tttkmbb.com/fitness/hiking-time","markdown":"https://tttkmbb.com/fitness/hiking-time.md","json":"https://tttkmbb.com/fitness/hiking-time.json","api":"https://tttkmbb.com/api/v1/calculate/hiking-time","schema":"https://tttkmbb.com/api/v1/calculators/hiking-time","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T03:47:36Z"}