Axle Load Calculator
Front and rear axle loads of a rigid vehicle from its unladen axle weights, wheelbase and each load’s mass and position, with margins against your limits.
Per-axle loads and gross weight, each load’s share on each axle, the combined centre of gravity, and margins against your own front, rear and gross limits — the lever rule, no legal tables.
Example: A 4 m wheelbase truck weighing 3,000 / 2,500 kg empty carries 4,000 kg centred 3 m behind the front axle: 1,000 kg goes to the front and 3,000 to the rear — 4,000 front, 5,500 rear, 9,500 gross.
A beam on two supports,
which is all a truck is.
The lever rule behind the numbers, what position means, and what the page will not decide.
The lever rule
A rigid vehicle rests on its front and rear axles like a beam on two supports. Taking moments about the rear axle, a load of mass m whose centre of gravity sits a distance x behind the front axle puts m × x ÷ wheelbase on the rear axle and the rest on the front. A load exactly over the rear axle goes entirely to the rear; one halfway goes half and half; one behind the rear axle takes weight off the front.
Positions and groups
Position is measured from the front axle to the load’s centre of gravity — the middle of a uniform pallet block, the marked CG of a machine. A tandem or tri-axle group is treated as one axle at its centre; how the group shares its load internally is not modelled. The unladen axle weights come from a weighbridge ticket, not from the vehicle’s plated figures.
Limits are yours
Legal axle limits, the plated weights and tyre ratings differ by country, vehicle and road, so the page embeds none; enter the ones that apply and it shows the margin. A negative axle load means the vehicle would tip — a geometry warning, not a legal one. Nothing leaves the browser; the same four anonymous usage counts as the rest of the site apply.
SOURCES
- Statics of a rigid beam on two supports: moments about the rear axle, rear share = mass × position ÷ wheelbase (any mechanics text); limits are user inputs, none embedded
Last reviewed 20 September 2026. How results are checked: How we verify.