A concrete ramp calculator returns the cubic yards of concrete needed to pour a ramp of any length, width, and rise. The geometry is a triangular wedge — half of length × width × rise — converted from cubic inches or cubic feet to cubic yards for ordering. The calculator also flags whether the slope meets ADA requirements (1:12 maximum, or 8.33% grade) for accessible ramps, and estimates total concrete cost based on 2026 ready-mix pricing.
Concrete ramps appear in many residential and light-commercial situations: accessible entry ramps for wheelchairs and walkers, loading ramps for warehouses and garages, transition ramps between elevations on a property, and approach ramps for sheds and outbuildings. The math is identical for all of them — what changes is the slope spec (steeper for utility ramps, gentler for ADA), the surface finish (broom finish for grip on pedestrian ramps), and any reinforcement (rebar mat for vehicle-rated ramps).
For ADA-compliant accessible ramps, the maximum slope is 1:12 (one inch of rise per 12 inches of run, or 8.33% grade). A 6-inch step requires at least 6 feet of ramp run; a 30-inch porch height requires at least 30 feet of run. Steeper slopes are permitted for non-ADA ramps but become difficult to navigate above 1:8 (12.5%) for pedestrians and above 1:6 (16.7%) for vehicles.
How to calculate concrete for a ramp
A ramp is a triangular wedge in cross-section. The volume formula is: volume = (1/2) × length × width × rise. All three dimensions must be in the same units; convert cubic inches to cubic yards by dividing by 46,656, or cubic feet to cubic yards by dividing by 27.
Worked example: a 12-foot-long, 4-foot-wide accessible ramp rising 12 inches (1 foot). Volume = 0.5 × 12 × 4 × 1 = 24 cubic feet = 0.89 cubic yards. Round up to 1 cubic yard for ordering. At 2026 ready-mix pricing of $150-200 per cubic yard delivered, the concrete alone costs $150-200, plus delivery fees and any short-load surcharges (most suppliers charge a short-load fee for orders under 3 cubic yards).
For a thicker reinforced ramp slab (typical for vehicle-rated ramps), add the slab thickness as a separate volume. A 12 ft × 4 ft × 4-inch concrete slab on top of the wedge adds 16 cubic feet = 0.59 cubic yards. Total order: 1.5 cubic yards.
Rebar reinforcement: a residential pedestrian ramp typically uses 6×6 W2.9×W2.9 welded wire mesh embedded in the slab. A vehicle-rated ramp uses #4 (1/2-inch) rebar in a 12-inch grid, plus an extra mat at any thickness transition. Rebar is sold by the pound or the lineal foot — your concrete calculator output gives you the slab area; multiply by 1.5 lf of rebar per sq ft for a 12-inch grid.
ADA slope requirements for accessible ramps
The Americans with Disabilities Act (ADA) Standards for Accessible Design specify a maximum running slope of 1:12 (8.33% grade) for all accessible ramps. Cross-slope (the slope perpendicular to the ramp direction, which affects drainage) cannot exceed 1:48 (2.08%).
Other ADA spec requirements: minimum clear width of 36 inches between handrails (so the ramp itself must be at least 42 inches wide to accommodate handrails on both sides). Maximum single-run length of 30 feet without a landing. Landing minimum 60 × 60 inches at top and bottom of every ramp. Handrails on both sides for any rise greater than 6 inches or any horizontal run greater than 72 inches. Edge protection (curbs or rails) preventing wheels from rolling off the side.
For non-ADA ramps (loading ramps, garage ramps, utility ramps), the slope can be steeper — but practical limits apply. Pedestrians struggle above 1:8 (12.5%); wheeled vehicles (carts, dollies) above 1:10 (10%); cars and small trucks above 1:6 (16.7%); heavy vehicles above 1:8 (12.5%). The calculator above flags the slope category so you know what your ramp will be usable for.
| Slope (rise:run) | Grade % | Use case | ADA? |
|---|---|---|---|
| 1:20 (5%) | 5.0% | Gentle accessible walkway; preferred for ADA | Yes |
| 1:16 (6.25%) | 6.25% | Comfortable accessible ramp | Yes |
| 1:12 (8.33%) | 8.33% | ADA maximum for new construction | Yes (max) |
| 1:10 (10%) | 10.0% | Existing buildings, very short rises only | Limited (existing only) |
| 1:8 (12.5%) | 12.5% | Loading ramps, utility carts | No |
| 1:6 (16.7%) | 16.7% | Vehicle ramps, garages | No |
| 1:4 (25%) | 25.0% | Steep utility, equipment-only | No |
Cost of a poured concrete ramp in 2026
Total concrete ramp cost in 2026 averages $8-15 per square foot of ramp surface for standard residential pedestrian ramps, or $12-25 per square foot for vehicle-rated reinforced ramps. The variation reflects ramp size (smaller ramps cost more per sq ft due to fixed setup costs), reinforcement spec, finish quality, and regional concrete prices.
A typical 4 ft × 12 ft accessible entry ramp: $400-700 in materials (concrete, rebar/mesh, form lumber, anchor bolts, broom finish) plus $400-1,200 in labour, total $800-1,900 installed. DIY material cost only: $200-400 for a basic mesh-reinforced ramp.
A typical 8 ft × 20 ft vehicle-rated garage ramp: $1,500-3,000 in materials plus $1,500-3,500 in labour, total $3,000-6,500 installed. The thicker slab and rebar reinforcement drive material cost up substantially vs a pedestrian ramp.
Ready-mix concrete pricing: $150-200 per cubic yard delivered in most U.S. metros (2026), plus short-load fees for orders under 3 cubic yards (typically $50-150). For very small ramps (under 1 cubic yard), bagged concrete from a home improvement store is sometimes cheaper than a short-load delivery — 80-lb bags of high-strength concrete cost $5-7 each and yield about 0.6 cubic feet per bag, so 24 cubic feet of ramp would need 40 bags at $200-280 plus your time mixing it.
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