{
  "slug": "swim-pace-converter",
  "title": "Swim Pace Converter (100m to 100y)",
  "category": "Swimming",
  "category_slug": "swimming",
  "tier": 2,
  "summary": "Convert swim pace between 100-meter and 100-yard intervals using the standard meter-yard ratio.",
  "description": "This calculator converts swim pace between 100-meter and 100-yard intervals using the international yard definition (1 yard = 0.9144 meters). It accepts a pace time in either seconds per 100 meters or seconds per 100 yards as input and returns the equivalent pace in the other unit. The conversion applies the standard meter-yard ratio, allowing swimmers to compare training times across pools measured in different distance systems.",
  "page_url": "https://fitmetriclab.com/en/tools/swimming/swim-pace-converter/",
  "api_url": "https://fitmetriclab.com/api/tools/swim-pace-converter.json",
  "formula": {
    "id": "swim_pace_converter",
    "expression": "T_{100m} = T_{100y} \\times \\frac{100}{91.44}",
    "variables": [
      {
        "symbol": "T_{100m}",
        "description": "Time per 100 m in seconds"
      },
      {
        "symbol": "T_{100y}",
        "description": "Time per 100 y in seconds"
      }
    ]
  },
  "inputs": [
    {
      "id": "sec_per_100m",
      "label": "Time per 100 m",
      "type": "number",
      "unit": "s",
      "default": 90,
      "min": 30,
      "max": 300,
      "step": 1
    },
    {
      "id": "sec_per_100y",
      "label": "Time per 100 y",
      "type": "number",
      "unit": "s",
      "default": 82,
      "min": 30,
      "max": 300,
      "step": 1
    }
  ],
  "worked_example": {
    "inputs": {
      "sec_per_100m": 90,
      "sec_per_100y": 82
    },
    "expected_output": "1:22 /100y"
  },
  "result_summary_template": "Given a swim pace of {sec_per_100m} seconds per 100 meters or {sec_per_100y} seconds per 100 yards, the converter applies the ratio 1 yard = 0.9144 meters to compute the equivalent pace in the opposite unit: {result}",
  "methodology": "Applies the standard conversion 1 yard = 0.9144 meters. For 100m to 100y: multiply time by 0.9144. For 100y to 100m: divide time by 0.9144. Based on the international yard definition adopted by the U.S. in 1959 (1 yd = 0.9144 m exactly).",
  "sources": [
    {
      "label": "National Institute of Standards and Technology. Handbook 44 – Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices. Appendix C: General Tables of Units of Measurement. 2023.",
      "url": "https://www.nist.gov/pml/weights-and-measures/publications/handbook-44"
    },
    {
      "label": "FINA. FINA Facilities Rules: Swimming Pools, Diving Pools, and Water Polo Pools. 2021.",
      "url": "https://www.worldaquatics.com/swimming/facilities"
    },
    {
      "label": "USA Swimming. USA Swimming Rules and Regulations. 2023.",
      "url": "https://www.usaswimming.org/utility/landing-pages/rules-regulations"
    }
  ],
  "faqs": [
    {
      "question": "Why is the conversion factor 0.9144?",
      "answer": "One yard is defined as exactly 0.9144 meters by international agreement (effective 1959). Since 100 yards equals 91.44 meters, swim pace over 100 yards covers 91.44% of the distance of 100 meters, resulting in a proportionally faster time for the same effort level."
    },
    {
      "question": "Does this conversion account for turns and push-offs?",
      "answer": "No. The calculator applies only the geometric distance ratio. Pool length affects the number of turns per lap; a 25-yard pool has more turns than a 50-meter pool for equivalent total distance, which can influence effective pace. The tool does not model these race-specific dynamics."
    },
    {
      "question": "Can I use this to predict race times in a different pool format?",
      "answer": "The conversion provides a baseline estimate assuming constant speed. Actual race performance depends on turn proficiency, breakout technique, pacing strategy, and conditioning. The tool offers a mathematical starting point but does not replace timed trials or coaching analysis."
    },
    {
      "question": "Which input field should I use?",
      "answer": "Enter your known pace in either the 100-meter or 100-yard field; the tool detects which value is provided and converts to the opposite unit. If both fields contain data, the calculator prioritizes the 100-meter input."
    },
    {
      "question": "How accurate is pace conversion for different strokes?",
      "answer": "The distance ratio applies equally to all strokes. Stroke-specific factors such as underwater dolphin kicks, breakout distances, and turn efficiency vary by individual and are not captured. The conversion remains geometrically valid but does not model stroke mechanics."
    }
  ],
  "related_tools": [
    {
      "slug": "swim-distance-converter",
      "title": "Swim Distance Converter",
      "api_url": "https://fitmetriclab.com/api/tools/swim-distance-converter.json",
      "page_url": "https://fitmetriclab.com/en/tools/swimming/swim-distance-converter/"
    },
    {
      "slug": "css-calculator",
      "title": "Critical Swim Speed (CSS) Calculator",
      "api_url": "https://fitmetriclab.com/api/tools/css-calculator.json",
      "page_url": "https://fitmetriclab.com/en/tools/swimming/css-calculator/"
    },
    {
      "slug": "swim-splits",
      "title": "Swim Split Calculator",
      "api_url": "https://fitmetriclab.com/api/tools/swim-splits.json",
      "page_url": "https://fitmetriclab.com/en/tools/swimming/swim-splits/"
    }
  ],
  "last_updated": "2026-04-22",
  "price": {
    "value": 0,
    "currency": "USD"
  },
  "runs_in_browser": true,
  "disclaimer": "Educational estimate produced from a published formula. Not medical, nutritional, or training advice. Calculations are deterministic — apply the formula to the inputs to reproduce the result."
}