Wheelchair ramp calculator. Enter the height from the ground to the top of the door threshold and read the ramp length, handrail need and materials cost.

Measure to the top of the threshold, not the porch deck. Example: 24.
Enter a rise in inches to see your ramp.
A long wooden wheelchair ramp with handrails on both sides leading to the porch of an American house
A long wooden wheelchair ramp with handrails on both sides leading to the porch of an American house

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A ramp needs 12 inches of length for every inch of rise, so a 24 inch porch step needs a 24 foot ramp. The calculator turns your measured rise into length, number of runs, handrail need and a materials-only cost range.

Wheelchair ramp calculator. Enter the height from the ground to the top of the door threshold and read the ramp length, handrail need and materials cost.

Measure to the top of the threshold, not the porch deck. Example: 24.
Enter a rise in inches to see your ramp.

Length is rise times 12, and each run stops at 30 inches of rise

Length comes from the 1:12 maximum running slope in the ADA standards, as summarized in the Access Board's ramp guide (Access Board, ramps). The same guide limits each run to 30 inches of rise, requires 36 inches of clear width between handrails, and requires handrails on both sides when the rise is more than 6 inches. Where a ramp turns, the intermediate landing must be at least 60 by 60 inches. A home is not bound by the ADA, but 1:12 is the steepest slope the standards allow, and a steeper ramp is harder for a wheelchair user to climb and for a caregiver to control going down.

Measure the rise from the ground to the top of the threshold, not the height of the porch deck.

The cost range covers materials only, not labor or permits

Cost is length multiplied by a per-foot materials range from Fixr's ramp cost guide, last updated January 31, 2025, read on 2026-10-31: $50 to $250 across materials, $100 to $250 for wood, $150 to $200 for aluminum and $200 to $250 for concrete (Fixr). Fixr is a secondary cost guide, not a quote. The figure excludes labor, which Fixr prices by the hour at $50 to $75 for carpentry and $60 to $90 for masonry, and it excludes permits, which Fixr does not list. Typical installed ramps in the guide run $1,700 to $5,000.

Permit rules and local codes vary, so ask your building department before you buy lumber.