Free outdoor calculators

The same calculators members use inside their modules, open to anyone. Each runs in your browser; the numbers you type never leave it.

OffRoad

Payload & GVWR margin — What is left of your payload once the build, the people, the water and the load are in.
Tongue weight & trailer balance — Whether your trailer is balanced into the 10–15% band, and what it costs your payload.
Tire pressure for load — Cold pressure for the weight a corner actually carries, rather than the placard figure for the tires the truck left the factory on.
Fuel range & reserve — Usable range after the terrain penalty and a reserve you do not plan to spend.
Speedometer & gearing correction — How far off your speedometer and odometer read after a tire size change, and the axle ratio that fixes it.
Recovery rigging — The force a pull will actually see, and whether the weakest rated component in your system covers it.

Rappel rope length — Whether the rope you have reaches the descent you are planning.
Fall factor — How hard a fall will hit, from the distance fallen and rope paid out.

Pack weight — Base weight plus consumables, checked against your body weight.
Water & food resupply — Total water and calories for the adventure, and when to plan a resupply.

Course Handicap — The strokes you receive on a specific set of tees, from the standard WHS formula.
Playing Handicap — The strokes you play off in a competition — your Course Handicap with the format allowance applied.
Playing Distance Adjustment — Elevation, wind, temperature and altitude adjustments to a flat yardage — a club-selection nudge.

Binding DIN setting — ISO 11088 weight-chart estimate of a starting release (DIN) value.
Tour time & daylight margin — Ascent and descent time against the daylight you have left.

Useful load — Occupants, baggage and fuel weight checked against the rated useful load.
Fuel & range — Planning and absolute endurance from usable fuel, burn rate and a reserve.
Crosswind component — Headwind and crosswind components from wind speed/direction and runway heading.

Kinetic energy & ethical range check — Impact energy from bullet weight and velocity, checked against a species floor.
Game pack-out — Pack adventures and total mileage to move a field-dressed animal to the trailhead.

Boat load capacity — Occupants, gear and fuel weight checked against your capacity plate rating.
Fuel range & endurance — Planning and absolute endurance from tank capacity, burn rate and a reserve.

Optics performance — Exit pupil, twilight factor and relative brightness for binoculars or a spotting scope.
Field of view & subject fill — Whether a lens is long enough for a subject at a given distance.

Weight cut planner — Total cut, weekly rate and a safe-rate check against your weight-class limit.
Round timer — Total work, rest and session length from rounds, round length and rest length.