Tools and calculators

A calculator is only as good as the method behind it. That’s why ours never stand alone: each one sits inside a guide that explains where its formulas come from (a standard, an official scale, a manufacturer’s data, or a government agency) and where its results stop being reliable. Units follow your edition, and nothing you enter ever leaves your browser.

The list grows as new guides are published.

• Hiking

  Calculate your hiking time

  Enter your route’s distance, elevation gain, and descent: the three methods in the table are calculated instantly.

  In the guide: Hiking Time: How to Estimate It Without Getting It Wrong

• Van life

  Calculate your battery capacity

  Use the total from your daily energy budget, in watt-hours, and the number of days the battery has to last without recharging.

  In the guide: House Battery Sizing: How to Calculate the Capacity Your Camper Van Needs

• Van life

  Calculate your panel’s output

  Pick the wattage of your flat-mounted panel, your daily consumption, the city closest to where you’re headed, and the month: you’ll get the average daily output and the wattage that would cover your consumption.

  In the guide: Van Solar Panels: How Many Watts You Need, Season by Season

• Trail running

  Calculate a race’s km-effort

  Enter the distance and elevation gain posted by the race organizer.

  In the guide: Km-Effort in Trail Running: The Math, ITRA Points, and Their Limits

• Snow

  Calculate the wind chill

  Enter the air temperature and wind speed from the forecast: you’ll get the wind chill and the frostbite risk for exposed skin.

  In the guide: Dressing for the Cold: The Three-Layer System Explained

• Snow

  Calculate your pole length

  Enter your height in inches (5 ft 7 in is 67 in): both lengths use Salomon’s ratios, as in the table, and poles are sold in centimeters.

  In the guide: Cross-Country Skiing: Classic or Skate? How to Choose as a Beginner

• Ocean

  Calculate your board volume

  Enter your weight and skill level: the volume comes from Firewire’s chart, interpolated between its rows.

  In the guide: Surfboard Volume: How to Calculate It From Your Weight and Skill Level