Net Force Calculator (Net Force Calculator)

Net force is the vector sum of all forces acting on an object. It is the net force that determines the object's acceleration under Newton's second law (F = m·a): not the largest individual force, but their combined result.

Resolve each force into components: Fx = F·cos θ and Fy = F·sin θ. Sum them: ΣFx and ΣFy. Net force magnitude = √(ΣFx² + ΣFy²), and its direction θ = atan2(ΣFy, ΣFx), measured counterclockwise from the +x axis.

ΣFx = 10·cos 0° + 10·cos 90° = 10 + 0 = 10 N. ΣFy = 10·sin 0° + 10·sin 90° = 0 + 10 = 10 N. Magnitude = √(10² + 10²) = √200 = 14.14 N. Direction = atan2(10, 10) = 45°. So the net force is 14.14 N at 45°.

Zero net force means the object is in equilibrium: its acceleration is zero. An object at rest stays at rest, and a moving object keeps moving in a straight line at constant speed (Newton's first law).

For collinear forces just use signs: take one direction as positive (+), the opposite as negative (−), then add algebraically. Example: 5 N right and 3 N left → 5 − 3 = 2 N to the right.

Newton (N), kilonewton (1 kN = 1000 N), and pound-force (1 lbf = 4.44822 N). All calculations are done consistently in the unit you choose.

Angles in degrees, measured counterclockwise from the +x axis (east = 0°, north = 90°, west = 180°, south = 270° or −90°). The resulting direction is normalized to (−180°, 180°].

None — resultant force is another name for net force: a single replacement vector with the same effect as all forces combined. What differs is the scalar sum of magnitudes (e.g. 10 N + 10 N = 20 N), which ignores direction and is not the net force.

Net force magnitude is never negative — always ≥ 0. What can be negative are its components (Fx or Fy), indicating that component points opposite the positive axis. In 1D mode, the result's sign shows direction: positive along the reference, negative opposite.