Ramp Length Calculator

Work out ramp length instantly with clear inputs, formula shown and shareable results.

About Ramp Length Calculator

Ramp length is the rise multiplied by the gradient denominator, so a 600 mm rise at 1 in 12 needs 7.2 metres of slope. Accessibility codes also cap the rise between landings, commonly 500 mm at 1 in 12 and 750 mm at 1 in 15, so a tall rise needs intermediate landings that add to the overall run.

Formulas

Ramp length

Length = rise x gradient denominator; gradient percent = 100 / denominator

Landings

Flights = ceil(rise / maximum rise per flight); landings = flights - 1

Worked example

With the default values below, Ramp Length Calculator returns Sloping ramp length of 7,200. Change any input above and every figure here is recalculated in your browser.

Inputs used

Total riseminimum 1 mm: 600 mm
Maximum gradientone of 1 in 12 — steepest generally permitted, 1 in 15 — preferred, 1 in 20 — no landings needed: 1 in 12 — steepest generally permitted
Landing lengthminimum 100 mm: 1,500 mm

Results

Sloping ramp length: 7,200 mm
Gradient: 8.33% %
Intermediate landings required: 1
Total length including landings: 8,700 mm

Step by step

1Values used
2Ramp length
3Landings
4Sloping ramp length= 7,200 mm
5Gradient= 8.33 %
6Intermediate landings required= 1
7Total length including landings= 8,700 mm

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Preliminary estimate only. Accessible ramp gradients, landings, widths and handrails must comply with the accessibility code adopted locally.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Preliminary estimate only. Accessible ramp gradients, landings, widths and handrails must comply with the accessibility code adopted locally.

Frequently Asked Questions

How is the Ramp Length figure worked out?

Length = rise x gradient denominator; gradient percent = 100 / denominator. Ramp length is the rise multiplied by the gradient denominator, so a 600 mm rise at 1 in 12 needs 7.2 metres of slope.

Why is a shallower ramp preferred?

A 1 in 12 slope is at the limit of what a manual wheelchair user can self-propel. At 1 in 20 no landings are required at all and the ramp is usable unaided by far more people.

What values do I need to enter?

This calculator takes 3 inputs: Total rise, Maximum gradient, Landing length. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.