About FreeFlight

Free flight runs on numbers as much as it runs on air — wing loading, glide ratio, sink rate, crosswind components, climb rates, harness fit. Most of it is simple arithmetic and trigonometry once you know the formula, but doing it by hand, or trying to recall a rule of thumb between packing up and driving to launch, is where it gets tedious. FreeFlight exists to take that arithmetic off your plate.

Instead of long articles you have to read end to end, the site is built around a set of small, single-purpose calculators, each aimed at one real question. The Wing Loading Calculator adds up your pilot, gear, and glider weight and divides by wing area to show your all-up wing loading in kg/m² and lb/ft². The Glide Ratio Calculator works out your still-air L/D from either a distance-and-height reading or an airspeed-and-sink-rate pair, with an optional wind adjustment. The Sink Rate Calculator turns an altitude lost and elapsed time into a rate in m/s and ft/min. The Wind Window & Crosswind Calculator splits a launch wind into headwind and crosswind components and checks them against general guidance bands by experience level. The Thermal Lift & Climb Rate Estimator turns an altitude gained while circling into a climb rate and a general strength read. And the Harness Sizing Guide suggests a general size band from your height and checks your all-up weight against it.

Beyond the calculators, the blog and learn section cover gear, flying technique, weather and thermals, and safety in plain language, and the Free Flight Museum is a browsable collection of the aircraft and pioneers behind paragliding, hang gliding, wingsuit flying, and the historic gliders that came before them, with every entry, image, and fact drawn from Wikipedia and Wikimedia Commons.

A few things worth stating plainly. FreeFlight is an independent site, not affiliated with any manufacturer, school, or governing body, and it does not teach anyone to fly. It is supported by advertising, which is how the tools stay free with no account required. Every calculator here produces a general estimate or a general guidance band, built on the numbers you enter and on widely-cited rules of thumb — not a certified figure for your specific equipment, and never a substitute for certified instruction and check flights with a qualified instructor. If a tool looks wrong, or there’s a calculator you wish existed, the contact page is the place to say so.