100% Free • Projectile Motion Apex, Time to Peak & Kinematics Solver

Maximum Height Calculator

Calculate projectile maximum apex height (H = h₀ + v₀²·sin²θ/2g), time to apex (t_apex = v₀·sinθ/g), horizontal range, flight time, and kinetic energy with the free Maximum Height Calculator.

Kinematics Presets:
28.0 m/s (100.8 km/h • 62.6 mph)
35.0° (0.611 rad)
0.00 m (0.00 ft)
9.80665 m/s²
Maximum Height 13.16 m
Time to Apex 1.64 s
Maximum Projectile Height (Apex H)
13.16 m

43.19 ft • Time to Apex: 1.64 s • Total Range: 75.09 m • Total Flight Time: 3.28 s

Time to Apex (t)
1.64 s

Vertical v_y = 0

Horizontal Range
75.09 m

246.36 ft

Total Flight Time
3.28 s

Ground impact

Apex Velocity (v_x)
22.94 m/s

82.6 km/h (51.3 mph)

Kinetic Energy @ Apex
67.1%

E_k = 1/2 m v_x²

Launch Speed (v₀)
28.0 m/s

100.8 km/h

Step-by-Step Maximum Height & Kinematics Derivation

What is Maximum Height in Projectile Motion? Kinematic Fundamentals

In classical Newtonian mechanics and kinematics, the maximum height (also known as the apex or vertical peak altitude, denoted as \(H\)) of a projectile is the highest vertical position reached along its curved parabolic path. At this instantaneous peak, the projectile's upward vertical motion ceases completely before gravitational acceleration pulls it downward:

1. Zero Vertical Velocity (\(v_y = 0\))

At the exact peak of flight, the vertical velocity component decelerates to zero: \(v_y(t_{\text{apex}}) = v_0 \sin\theta - g t_{\text{apex}} = 0\).

2. Constant Horizontal Velocity (\(v_x\))

In the absence of air resistance, the horizontal velocity component remains constant throughout the entire trajectory: \(v_x = v_0 \cos\theta\).

3. Energy Transformation

All vertical kinetic energy (\(\frac{1}{2} m v_{0y}^2\)) is converted into maximum gravitational potential energy (\(m g \Delta h\)).

The Core Mathematical Formulas for Maximum Height, Apex Time & Range

Summary of the foundational kinematic equations used across physics, ballistics, and sports:

Kinematic Metric Mathematical Formula SI Units & Description
Maximum Apex Height (\(H\)) $$H = h_0 + \frac{v_0^2 \sin^2\theta}{2g}$$ \(\text{meters (m)} \equiv \text{feet (ft)}\)
Time to Reach Apex (\(t_{\text{apex}}\)) $$t_{\text{apex}} = \frac{v_0 \sin\theta}{g}$$ \(\text{seconds (s)}\)
Horizontal Velocity at Apex (\(v_x\)) $$v_x = v_0 \cos\theta$$ \(\text{m/s} \equiv \text{ft/s}\)
Total Flight Time (\(T_{\text{total}}\)) $$T = \frac{v_0 \sin\theta + \sqrt{(v_0 \sin\theta)^2 + 2 g h_0}}{g}$$ \(\text{seconds (s)}\)
Total Horizontal Range (\(R\)) $$R = v_0 \cos\theta \times T_{\text{total}}$$ \(\text{meters (m)}\)
Inverse Velocity Solver (\(v_0\)) $$v_0 = \frac{\sqrt{2g(H - h_0)}}{\sin\theta}$$ \(\text{m/s}\)

How to Use the Maximum Height Calculator

1 Select Calculation Method

Choose between Forward Kinematics (Solve Height \(H\)), Inverse Velocity Solver (\(v_0\)), or Inverse Angle Solver (\(\theta\)).

2 Enter Initial Velocity & Angle

Input launch velocity in \(\text{m/s}\), \(\text{km/h}\), \(\text{ft/s}\), or \(\text{mph}\) and angle in degrees or radians.

3 Specify Initial Height & Gravity Field

Input release elevation (\(h_0\)) and select gravity field (Earth, Moon, Mars, Jupiter, or Custom).

4 Review Apex Metrics & Live Derivations

Inspect peak altitude, flight duration, apex speed, kinetic energy ratio, and step-by-step KaTeX mathematical derivations.

Why Launch Angle Matters: 45° Maximum Range vs. 90° Maximum Height

How angular trajectory trade-offs dictate vertical altitude versus horizontal distance:

90° Pure Vertical Launch (Maximum Height)

Because \(\sin(90^\circ) = 1.0\), \(100\%\) of initial kinetic energy is directed into vertical ascent: \(H_{\text{max}} = h_0 + \frac{v_0^2}{2g}\).

45° Optimal Ground Launch (Maximum Range)

Splits initial velocity equally between vertical and horizontal components (\(v_{0x} = v_{0y} = v_0 / \sqrt{2}\)), producing exactly \(50\%\) of vertical max height while maximizing horizontal range: \(R = \frac{v_0^2}{g}\).

The Effect of Initial Elevation (\(h_0\)): Ground Level vs. Cliff Launches

Accounting for launch platforms, buildings, and human release heights:

When launching from an elevated platform of height \(h_0\), the time to reach the apex (\(t_{\text{apex}}\)) and the relative height above the launch point (\(\Delta H = \frac{v_0^2 \sin^2\theta}{2g}\)) remain identical to a ground-level launch. However, the total altitude above the ground is the direct sum \(H_{\text{total}} = h_0 + \Delta H\), and the falling phase after the apex lasts longer due to the extra descent distance.

Key Features of the Maximum Height Calculator

Multi-Variable Kinematics Solver

Solve for apex height (\(H\)), required launch velocity (\(v_0\)), or launch angle (\(\theta\)) with automatic unit conversions.

Multi-Body Planetary Gravity

Evaluate trajectories under Earth (\(9.807\text{ m/s}^2\)), Moon (\(1.62\text{ m/s}^2\)), Mars (\(3.71\text{ m/s}^2\)), or Jupiter (\(24.79\text{ m/s}^2\)).

Elevated Platform Launch Modeling

Accommodates non-zero launch heights (\(h_0\)) with full quadratic descent time solutions.

Mechanical Energy Breakdown

Computes horizontal velocity and kinetic energy retention ratio at the parabolic apex.

Step-by-Step KaTeX Derivations

Renders clear algebraic proofs with live numeric substitutions for physics coursework.

100% In-Browser & Private

Runs instantly on any smartphone, tablet, or desktop with zero server lag and total calculation privacy.

Problems This Maximum Height Calculator Solves

Eliminates Trigonometric Dimensional Errors

Prevents common student errors when squaring trigonometric terms (\(\sin^2\theta\)) and converting between degrees and radians.

Solves Asymmetric Elevated Launches Instantly

Eliminates tedious manual quadratic formula factoring when calculating flight time and range from elevated cliffs (\(h_0 > 0\)).

Celestial Gravity Comparison: How High Can You Throw on the Moon or Mars?

Comparing maximum height scaling across the solar system for a standard \(20\text{ m/s}\) throw at \(45^\circ\):

Celestial Body Gravity (\(g\)) Apex Height (\(H\)) Time to Apex Relative Height Factor
Earth \(9.81\text{ m/s}^2\) \(10.19\text{ m}\) \(1.44\text{ s}\) \(1.00\times\) (Baseline)
Moon \(1.62\text{ m/s}^2\) \(61.73\text{ m}\) \(8.73\text{ s}\) \(6.05\times\text{ Higher}\)
Mars \(3.71\text{ m/s}^2\) \(26.95\text{ m}\) \(3.81\text{ s}\) \(2.64\times\text{ Higher}\)
Jupiter \(24.79\text{ m/s}^2\) \(4.03\text{ m}\) \(0.57\text{ s}\) \(0.40\times\text{ Lower}\)

Aerodynamic Drag & Atmospheric Air Resistance Realities

Why real-world projectiles fall short of ideal vacuum maximum height:

In real atmospheric conditions, quadratic air drag force (\(F_d = \frac{1}{2} \rho v^2 C_d A\)) continuously opposes the projectile's velocity vector. On high-speed objects like baseballs or golf balls, air resistance reduces peak apex height by \(15\%\text{ to }35\%\) compared to the ideal vacuum equation, while shifting the trajectory apex slightly forward along the flight path.

Conservation of Mechanical Energy: Kinetic vs. Potential Energy Partition at Apex

How initial kinetic energy partitions perfectly between horizontal motion and gravitational altitude:

Gravitational Potential Energy at Apex

The vertical kinetic energy converts entirely into potential energy: \(E_{p,\text{apex}} = m g (H - h_0) = E_{k,0} \sin^2\theta\).

Retained Kinetic Energy at Apex

Because horizontal velocity is invariant (\(v_x = v_0 \cos\theta\)), the projectile retains kinetic energy: \(E_{k,\text{apex}} = \frac{1}{2} m v_x^2 = E_{k,0} \cos^2\theta\).

Sports Biomechanics: Optimizing Apex Height in Basketball, Soccer & Baseball

How athletes adjust launch angle and velocity to control trajectory apex:

In basketball, shooters aim for a \(45^\circ\text{ to }55^\circ\) release angle (producing an apex altitude of approximately \(4.5\text{ to }5.0\text{ meters}\)) because a steeper descent angle widens the effective elliptical cross-section of the 18-inch rim, significantly increasing shooting percentage. In soccer, free-kick specialists launch at \(30^\circ\text{ to }38^\circ\) to clear the defensive wall while diving under the crossbar.

Aerospace Kinematics: Suborbital Sounding Rocket Apogee Altitude

Calculating maximum altitude after rocket booster motor burnout:

For sounding rockets and ballistic missiles, powered ascent terminates at motor burnout altitude (\(y_{\text{bo}}\)) with burnout velocity (\(v_{\text{bo}}\)). The unpowered ballistic coast to peak apogee is governed directly by kinematics:

$$H_{\text{apogee}} = y_{\text{bo}} + \frac{v_{\text{bo}}^2 \sin^2\theta}{2 g_{\text{eff}}}$$

Projectile Motion on an Inclined Plane: Uphill & Downhill Slopes (\(\alpha\))

Deriving apex height perpendicular to an inclined mountain slope:

When firing a projectile at angle \(\theta\) along a hill inclined at angle \(\alpha\), the gravity vector resolves into components parallel (\(g \sin\alpha\)) and perpendicular (\(g \cos\alpha\)) to the slope. The maximum perpendicular height above the incline is:

$$H_{\text{perp}} = \frac{v_0^2 \sin^2(\theta - \alpha)}{2 g \cos(\alpha)}$$

The Parabola of Safety: Bounding Envelope of All Reachable Trajectories

The theoretical protective boundary for all launch angles fired at speed \(v_0\):

For any fixed initial speed \(v_0\), varying the launch angle \(\theta\) from \(0^\circ\) to \(90^\circ\) generates a family of intersecting parabolas. The mathematical envelope enclosing all possible trajectories defines the Parabola of Safety:

$$y_{\text{envelope}} = \frac{v_0^2}{2g} - \frac{g x^2}{2 v_0^2}$$

Any point located outside this bounding parabola is physically unreachable, defining the safety exclusion zone used in explosive quarry blasting and artillery defense planning.

The Magnus Effect: How Aerodynamic Spin Modifies Projectile Apex Height

How backspin and topspin alter apex altitude and parabolic curvature:

Backspin (Upward Aerodynamic Lift)

In golf driver shots and baseball pitches, rapid backspin creates high pressure below and low pressure above the ball, generating upward lift (\(\vec{F}_L = S(\vec{\omega} \times \vec{v})\)) that increases apex height by up to \(30\%\).

Topspin (Downward Aerodynamic Force)

In tennis and table tennis groundstrokes, topspin drives airflow faster underneath the ball, generating downward lift that suppresses apex height and forces a sharp, rapid dive into the opponent's court.

Frequently Asked Questions

Comprehensive answers to common questions about projectile maximum height formulas, time to peak apex, initial velocity calculations, and kinematics.