{
    "name": "Pace Calculator",
    "url": "https://calculators.geekmidst.com/calculators/pace-calculator",
    "markdown": "https://calculators.geekmidst.com/calculators/pace-calculator.md",
    "category": "Health & fitness",
    "description": "Enter any two of distance, time and pace to work out the third, in minutes per km or per mile, with speed and finish times for common race distances.",
    "summary": "Pace is time divided by distance. Give any two of distance, finish time and pace, leave the third blank, and the calculator solves for it.",
    "also_called": [
        "Running pace calculator",
        "Race time calculator"
    ],
    "applies_to": "Worldwide",
    "last_updated": "2026-10-29",
    "computation": "Results are computed in the visitor’s browser on the HTML page. This API describes the calculator; it does not compute results.",
    "inputs": [
        {
            "name": "race",
            "label": "Distance",
            "type": "select",
            "default": "custom",
            "options": {
                "custom": "Enter distance",
                "5k": "5 km",
                "10k": "10 km",
                "half": "Half marathon (21.0975 km)",
                "marathon": "Marathon (42.195 km)"
            }
        },
        {
            "name": "distance",
            "label": "Custom distance",
            "type": "number",
            "default": "10",
            "optional": true,
            "shown_when": {
                "race": "custom"
            }
        },
        {
            "name": "distance_unit",
            "label": "Distance in",
            "type": "segmented",
            "default": "km",
            "options": {
                "km": "Kilometres",
                "mi": "Miles"
            },
            "shown_when": {
                "race": "custom"
            }
        },
        {
            "name": "hours",
            "label": "Time: hours",
            "type": "number",
            "default": "0",
            "unit": "h",
            "optional": true
        },
        {
            "name": "minutes",
            "label": "Minutes",
            "type": "number",
            "default": "50",
            "unit": "min",
            "optional": true
        },
        {
            "name": "seconds",
            "label": "Seconds",
            "type": "number",
            "default": "0",
            "unit": "s",
            "optional": true
        },
        {
            "name": "pace_min",
            "label": "Pace: minutes",
            "type": "number",
            "default": "",
            "unit": "min",
            "optional": true
        },
        {
            "name": "pace_sec",
            "label": "Pace: seconds",
            "type": "number",
            "default": "",
            "unit": "s",
            "optional": true
        },
        {
            "name": "pace_unit",
            "label": "Pace per",
            "type": "segmented",
            "default": "km",
            "options": {
                "km": "Kilometre",
                "mi": "Mile"
            }
        }
    ],
    "outputs": [
        {
            "key": "result",
            "label": "Result",
            "format": "text"
        },
        {
            "key": "pace_km",
            "label": "Pace per km",
            "format": "text"
        },
        {
            "key": "pace_mi",
            "label": "Pace per mile",
            "format": "text"
        },
        {
            "key": "time",
            "label": "Time (h:mm:ss)",
            "format": "text"
        },
        {
            "key": "speed_kmh",
            "label": "Speed",
            "format": "number"
        },
        {
            "key": "speed_mph",
            "label": "Speed",
            "format": "number"
        },
        {
            "key": "distance_km",
            "label": "Distance",
            "format": "number"
        },
        {
            "key": "distance_mi",
            "label": "Distance",
            "format": "number"
        }
    ],
    "formula": {
        "text": "Pace = Time ÷ Distance;  Time = Pace × Distance;  Distance = Time ÷ Pace;  Speed (km/h) = 60 ÷ pace (min/km)",
        "variables": {
            "1 mile": "1.609344 km (exact)",
            "half marathon": "21.0975 km",
            "marathon": "42.195 km"
        }
    },
    "worked_example": {
        "inputs": {
            "race": "custom",
            "distance": "10",
            "distance_unit": "km",
            "hours": "0",
            "minutes": "50",
            "seconds": "0",
            "pace_min": "",
            "pace_sec": "",
            "pace_unit": "km"
        },
        "steps": [
            "50 minutes = 3,000 seconds; 3,000 ÷ 10 km = 300 s = 5:00 per km.",
            "Per mile: 300 × 1.609344 = 482.8 s ≈ 8:03 per mile.",
            "Speed = 60 ÷ 5 = 12 km/h = 12 ÷ 1.609344 = 7.46 mph."
        ],
        "result": "Running 10 km in 50 minutes is a pace of 5:00 per km (8:03 per mile), or 12 km/h."
    },
    "interpretation": "The finish-time table assumes you can hold the same pace for longer distances, which few runners can. As a rough guide, expect your pace to slow as the distance increases, especially beyond the half marathon.",
    "assumptions": [
        "Even pace throughout.",
        "Paces and times are rounded to the nearest second."
    ],
    "limitations": [
        "Does not adjust for hills, heat, wind or fatigue.",
        "GPS distance can differ from the officially measured course, so watch pace and official pace may not match exactly."
    ],
    "rules": null,
    "faqs": [
        {
            "question": "What pace is a sub-4-hour marathon?",
            "answer": "Just under 5:41 per km (9:09 per mile): 42.195 km at 5:41 per km takes 3:59:48."
        },
        {
            "question": "How do I convert pace per km to pace per mile?",
            "answer": "Multiply the pace in seconds by 1.609344. For example, 5:00 per km is 300 s × 1.609344 = 483 s, or 8:03 per mile."
        }
    ],
    "sources": [],
    "related": [
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            "name": "Calories Burned Calculator",
            "url": "https://calculators.geekmidst.com/calculators/calories-burned-calculator"
        },
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            "url": "https://calculators.geekmidst.com/calculators/length-converter"
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            "name": "Carbohydrate Calculator",
            "url": "https://calculators.geekmidst.com/calculators/carbohydrate-calculator"
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        {
            "name": "Date Difference Calculator",
            "url": "https://calculators.geekmidst.com/calculators/date-difference-calculator"
        }
    ],
    "disclaimer": null,
    "publisher": "GM¹X CalcVerse"
}