Accessible ramp planning

Wheelchair Ramp Length Calculator

Estimate how long a wheelchair ramp needs to be from the rise and slope you choose. Get the horizontal run, surface length, slope angle, landing notes, handrail triggers, and a rough material budget for early planning.

Ramp run 24 ft 24 in rise at a 12:1 slope, about 4.8°.
Ramp size

A 12:1 setting means 12 inches of horizontal run for every 1 inch of rise. Public accessibility projects often use 12:1 or gentler, plus landings and other details.

Budget estimate

Use the budget fields for quick comparisons only. Wood, aluminum modular ramps, handrails, permits, site prep, and labor vary widely.

How to use the wheelchair ramp calculator

  1. Measure the vertical rise from the lower walking surface to the top landing or doorway threshold.
  2. Choose the slope ratio. A larger number gives a longer, gentler ramp.
  3. Enter the clear ramp width you are planning between rails or edge protection.
  4. Adjust the cost fields if you want a rough comparison between ramp layouts.

The calculator shows the ramp run before separate flat landing space. Many real layouts need a level landing at the top, a level landing at the bottom, and an intermediate landing when the rise is large or the ramp turns.

Wheelchair ramp length examples

At a 12:1 slope, every inch of rise needs about 1 foot of ramp run. A 6 inch threshold needs about 6 feet, a 24 inch porch needs about 24 feet, and a 30 inch deck needs about 30 feet of run before adding landing space.

A gentler 14:1 slope can feel easier to roll but takes more yard or driveway space. A steeper slope may be suitable only for limited residential situations or assisted portable-ramp use. When safety or code compliance matters, verify the final plan locally.

Related project calculators

Shed ramp slope calculator Deck stair stringer calculator Concrete step calculator Deck post spacing calculator

Wheelchair ramp FAQ

How long is a ramp for a 24 inch rise?

At a 12:1 slope, a 24 inch rise needs 288 inches, or 24 feet, of horizontal run. Add level landing space separately.

What is the difference between ramp run and ramp surface length?

Run is the horizontal distance on the ground. Surface length is the sloped board, metal ramp, or walking surface length. Surface length is slightly longer because it follows the diagonal.

When does a wheelchair ramp need handrails?

Many accessibility rules require handrails when a ramp rises more than 6 inches or runs more than 72 inches, but requirements vary by project and location. Use the result as an early planning flag, not a final ruling.

How wide should a wheelchair ramp be?

A 36 inch clear width is a common planning minimum for accessible routes. Some residential, modular, or local-code situations may require a different width, especially around handrails, turns, and landings.