How to calculate acceleration from velocity change and time
Enter a velocity change and elapsed time, or let the calculator find the change from Initial velocity (v₀) and Final velocity (v₁). It reports average acceleration in m/s^2, ft/s^2, and g, then lists the formula and conversion steps used.
Enter the values in the calculator
- Select Direct velocity change when the change is already known.
- Select Initial & final velocity when you have both values, then fill in Initial velocity (v₀) and Final velocity (v₁).
- Enter the velocity value or values, choose a Velocity unit, enter Time (Δt), and choose a Time unit.
- Click Calculate to show Result and Formula & steps.
How the acceleration calculation works
The calculator uses a = Δv / Δt. In Initial & final velocity mode, it first calculates Δv = v₁ - v₀. It then converts velocity to meters per second and time to seconds before dividing.
Velocity change: 20 m/s
Time: 4 s
Acceleration: 5 m/s^2
In ft/s^2: 16.404199
In g: 0.509859 gVelocity accepts meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), feet per second (ft/s), or knots (kn). Time accepts seconds (s), minutes (min), or hours (h).
Input limits and signed results
Time must be greater than zero. The calculator rejects empty fields, scientific notation, other non-decimal text, non-finite values, and absolute input values above 1e12. In Initial & final velocity mode, both velocity fields use the selected Velocity unit.
The result is average acceleration along the signed direction in your inputs. A negative result can describe a change toward the negative direction; its relation to slowing down depends on which direction you set as positive. The calculation uses one signed scalar axis and leaves two-dimensional and three-dimensional vector components unresolved.
Copy, download, or reset a result
After Calculate, Copy result puts the plain-text result on the clipboard. Download result (.txt) creates a text file. If copying fails, the text result becomes available for manual selection. Editing an input hides the current result until you calculate again.
Reset clears the value fields, selects Direct velocity change, restores Meters per second (m/s) and Seconds (s), and hides the result. The calculation runs in the browser, and the entered values and result are not submitted to a server.
Read the three result units
The main Acceleration value uses meters per second squared. In ft/s² converts that same value to feet per second squared. In g divides by standard gravity, shown in the label as 9.80665 m/s².
For example, 20 m/s over 4 s gives 5 m/s². The same calculation displays 16.404199 ft/s² and 0.509859 g in the result panel.
Choose a calculator for another quantity
Browse Science Calculators for other science formulas. Use the Force Calculator when mass and acceleration are known and force is unknown. Use the Momentum Calculator for linear momentum from mass and velocity. The Physics Calculator covers calculations involving several physics quantities.
Frequently asked questions
How do I calculate acceleration from velocity and time?
Divide the change in velocity by elapsed time with a = Δv / Δt. Enter the change directly, or let Initial & final velocity calculate it from the two velocity fields.
Can I calculate acceleration from initial and final velocity?
Yes, select Initial & final velocity and enter both values in the selected Velocity unit. The calculator subtracts Initial velocity (v₀) from Final velocity (v₁) before applying the formula.
What units does the acceleration calculator accept?
Velocity accepts m/s, km/h, mph, ft/s, and knots. Time accepts seconds, minutes, and hours, and the result is reported in m/s^2, ft/s^2, and g.
Why is my acceleration result negative?
A negative result means the calculated change points in the negative direction of your signed values. It does not automatically mean the object is slowing down.
Does this calculator calculate 2D or 3D acceleration?
No, it uses signed scalar velocity values along one axis. It does not resolve vector components in two or three dimensions.