AbraCalc

Projectile Range Calculator

Calculate the horizontal range, maximum height and time of flight of a projectile launched from flat ground using R = v₀²sin(2θ)/g. Distinct from the trajectory plotter — this gives numerical answers only.

Embed this tool on your site

How to use this tool

  1. Enter launch velocity v₀, launch angle θ and gravity g in the fields above.
  2. Results update instantly as you type — or click Calculate.
  3. Read your horizontal range and the full breakdown beneath it.

For a projectile launched from level ground: R = v₀²sin(2θ)/g. Maximum range occurs at θ = 45°. Max height: H = v₀²sin²θ/(2g). Time of flight: T = 2v₀sinθ/g. Ignores air resistance.

Formula

Horizontal range: R = v02 × sin(2θ) / g

Maximum height: H = v02 × sin2(θ) / (2g)

Time of flight: T = 2 v0 sin(θ) / g

How it works

This calculator uses the standard kinematic equations for a projectile launched from flat ground with initial speed v0 at angle θ above horizontal, under constant gravitational acceleration g. Air resistance is ignored, so results represent the ideal vacuum trajectory. The maximum possible range at a given speed occurs at exactly 45° and equals v02/g.

Worked example

Worked example

  1. Inputs: v₀ = 20 m/s, θ = 45°, g = 9.81 m/s². Convert angle to radians: 45 × π/180 = 0.7854 rad.
  2. Range: R = 20² × sin(90°) / 9.81 = 400 × 1 / 9.81 = 40.775 m.
  3. Max height: H = 400 × sin²(45°) / (2 × 9.81) = 400 × 0.5 / 19.62 = 10.194 m.
  4. Time of flight: T = 2 × 20 × sin(45°) / 9.81 = 40 × 0.7071 / 9.81 = 2.884 s.

Horizontal range = 40.775 m; maximum height = 10.194 m; time of flight = 2.884 s.

Key terms

Launch velocity (v₀)
The speed of the projectile at the moment of launch, before gravity acts on it.
Launch angle (θ)
The angle above the horizontal at which the projectile is fired. 45° maximises range on flat ground.
Time of flight
The total time the projectile is in the air from launch until it returns to the same height.
Maximum height
The peak vertical position reached during the trajectory, where vertical velocity is momentarily zero.
Gravitational acceleration (g)
The downward acceleration due to gravity; approximately 9.81 m/s² on Earth's surface.

Frequently asked questions

How does this differ from the projectile motion calculator?
That tool plots the trajectory chart and supports non-zero launch height. This calculator focuses on exact numerical outputs from the standard range formula.
What launch angle gives the greatest range?
45° on flat ground with no air resistance. Air resistance shifts the optimal angle slightly below 45°.

References & sources