How We Calculate

How the Adventure Calcs tools work, where the rules and prices come from and what the results can and cannot tell you.

Our approach

A calculator is only useful if you can see how it reached its answer. Each Adventure Calcs page explains its method in plain language, names the formulas and published figures behind it and tells you which numbers are defaults you should replace. We use published formulas and public sources, we avoid hidden assumptions and we do not let advertising change a result.

Airline bags and fees

The bag tools apply each airline’s own published baggage rules and fees to the bags you enter, including overweight and oversize charges and personal item dimensions. Linear inches, the measure behind the 62-inch checked-bag limit many airlines use, is length plus width plus height. Airline rules vary by fare, route and loyalty status, so each page links the airline’s own page.

TSA and airports

Security answers follow the TSA’s published rules, including the 3-1-1 rule for liquids (containers of 3.4 ounces or less in one quart-size bag), and the can-I-bring-it finder points to the TSA for the final word. Airport parking compares on-site, off-site and rideshare costs using published rates and your trip length. Flight time uses the great-circle (Haversine) distance between airport coordinates plus an allowance, with a cruise speed you can edit, and jet lag recovery uses the number of time zones you cross.

Trip and cruise costs

Trip cost tools add up lodging, food, transport and activities using your inputs and published reference prices, such as the U.S. General Services Administration’s per diem rates for lodging and meals and incidental expenses and the National Park Service’s entrance fees and pass prices. The pass break-even tool compares your expected visits with the price of a pass. Cruise tools add fares, taxes, gratuities, drink packages, excursions and port costs from each cruise line’s published pricing. Prices change with season and demand, so treat results as planning figures.

Expat and moving costs

Cost-of-living tools use published and crowd-sourced data from sources such as Numbeo and International Living, convert currencies with European Central Bank rates and show a runway: your savings divided by your monthly costs. The moving tools compare a local, long-distance or international move across movers, a rental truck and a container.

Entry rules

Visa and entry answers come from the U.S. Department of State and destination governments. The Schengen calculator applies the rule of 90 days in any 180-day period by counting the days you list. Entry rules change and depend on your passport, purpose and length of stay, so confirm with the official government page before you travel.

Adventure and converters

Camping, bike and climbing tools use standard sizing and planning rules, such as gear ratio (the chainring teeth divided by the cog teeth) and bike frame size from your body measurements. Converters use exact conversion factors. For climbing and bike equipment, always follow the manufacturer’s instructions.

Quizzes

The eight quizzes ask a few short questions and match you to a result such as a beginner outdoor sport, a cruise cabin, a retirement destination or a cruise excursion, using fixed rules. They are a starting point, and your answers travel in the result page’s address, which the privacy policy explains.

Limits

Travel rules and prices move faster than any website. Use the results to plan, then confirm the current rule or price with the airline, airport, cruise line or government before you book, pay or pack.