About the SUVAT Calculator
Solves the five kinematics equations for constant acceleration, given any 3 of the 5 variables.
What it is
Enter any 3 of displacement (s), initial velocity (u), final velocity (v), acceleration (a), and time (t), and the calculator automatically selects the correct SUVAT equation(s) to solve for the remaining 2, showing the full algebraic substitution.
Key features
5-variable input
Fill in any 3 of the 5 fields; the other 2 are left blank and solved automatically.
Automatic equation selection
Picks the SUVAT equation combination that avoids requiring an unknown as input.
Step-by-step substitution
Shows the exact equation and numbers used for each unknown.
Quadratic time handling
When s, u, a are known, solving for t is quadratic — both physically valid roots are shown.
Negative-value support
Deceleration and negative displacement are handled correctly with sign conventions explained.
Consistency validation
Physically inconsistent combinations (negative discriminants, negative times) are flagged rather than shown as a wrong answer.
The five SUVAT equations
v = u + at · s = ut + ½at² · v² = u² + 2as · s = ((u+v)/2)t · s = vt − ½at²