Velocity Calculator
Instantly calculate final velocity, average speed, and distance travelled using initial velocity, acceleration, and time.
Calculate Final Velocity
Enter your known kinematic variables below to instantly solve for final velocity and total distance travelled.
Kinematics Solver
Calculate velocity and displacement using standard physics equations.
How it Works
Understanding the physics behind the calculator
Set Initial Velocity
Enter the starting speed of the object. If it starts from a standstill, leave this as 0 m/s.
Define Acceleration
Input the rate of change of velocity. Use 9.81 for free-falling objects on Earth, or a negative value for deceleration.
Input Time
Specify the duration (in seconds) over which the acceleration is applied to the object.
View Results
Instantly see the final velocity in multiple units (m/s, km/h, mph) and the total distance covered.
Kinematic Equations & Units
A general overview of the standard equations of motion used for objects moving with constant acceleration.
| Variable | Symbol | SI Unit | Description |
|---|---|---|---|
| Initial Velocity | u (or v₀) | metres per second (m/s) | The speed and direction of the object at the start of the time period. |
| Final Velocity | v | metres per second (m/s) | The speed and direction of the object at the end of the time period. |
| Acceleration | a | metres per second squared (m/s²) | The rate at which velocity changes over time. Gravity on Earth is ~9.81 m/s². |
| Time | t | seconds (s) | The duration over which the acceleration is applied. |
| Displacement | s (or d) | metres (m) | The overall change in position of the object (distance in a specific direction). |
1. Final Velocity: v = u + at
2. Displacement: s = ut + ½at²
3. Average Velocity: v_avg = (u + v) / 2
Velocity & Kinematics FAQ
Answers to the most frequently asked questions about velocity, speed, and the equations of motion.
The formula for final velocity is v = u + at, where ‘v’ is the final velocity, ‘u’ is the initial velocity, ‘a’ is the constant acceleration, and ‘t’ is the time elapsed.
Speed is a scalar quantity that refers to how fast an object is moving, regardless of direction (e.g., 50 mph). Velocity is a vector quantity that refers to the rate at which an object changes its position, meaning it includes both speed and direction (e.g., 50 mph North).
The standard International System of Units (SI) unit for velocity is metres per second (m/s). It can also be expressed in kilometres per hour (km/h) or miles per hour (mph) depending on the regional or practical context.
You can calculate the distance (displacement) using the kinematic equation: s = ut + ½at², where ‘s’ is distance, ‘u’ is initial velocity, ‘a’ is acceleration, and ‘t’ is time. This calculator computes this automatically for you.
Yes. Because velocity is a vector, a negative value simply indicates that the object is moving in the opposite direction to the one defined as positive. Similarly, negative acceleration (deceleration) means the object is slowing down in the positive direction, or speeding up in the negative direction.
