Car Park Ramp & Transition Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
Ramp inputs
Profiles are labels only (reviewed 2026-06-23). Standards such as AS/NZS 2890.1 are project/council-specific — confirm with a traffic engineer or certifier. Runs in your browser.
Result
| Segment | Grade | Length | Δ | Start RL | End RL |
|---|---|---|---|---|---|
| Top transition | 1:10 | 2 m | 0.2 m | 100 | 99.8 |
| Main ramp | 1:5 | 10 m | 2 m | 99.8 | 97.8 |
| Bottom transition | 1:10 | 2 m | 0.2 m | 97.8 | 97.6 |
Ramp: 2 m @ 1:10, 10 m @ 1:5, 2 m @ 1:10, total 14 m.
How to use this calculator
- Enter the total height change, the main ramp grade (1:N or %), and the length and grade of the top and bottom transition zones.
- Set the top RL and the direction (down or up ramp).
- Read the main ramp length, total length, the segment schedule with RLs and a longitudinal section — then copy the drawing note.
How it works
Each transition zone changes height by its length × grade. The transitions are taken off the total height first; the remaining height is covered by the main ramp, whose run = remaining height ÷ main grade decimal (1:N → 1/N).
The overall length is the sum of the three segment lengths, and RLs are stepped through each segment. The tool warns if the transitions use up the whole height, if the main grade is zero, or if the main length would go negative.
Worked example
2.4 m drop, two 2 m @ 1:10 transitions, 1:5 main. The transitions account for 0.4 m, leaving a 2.0 m main drop. Main run = 2.0 ÷ (1/5) = 10.0 m, so the total run is 2 + 10 + 2 = 14.0 m.
Common mistakes
- Forgetting the top and bottom transition zones — they shorten the main ramp and add to the total length.
- Letting the transitions consume more height than the total — then there's nothing left for the main ramp.
- Treating the result as compliant. Car-park ramp standards are project and council specific.
Frequently asked questions
What is a transition zone?
A shorter, gentler grade at the top and bottom of a ramp so vehicles don't scrape as they change slope. The transitions take some of the height, so the main ramp is shorter than the full height ÷ grade.
Why does a ramp need top and bottom transitions?
To avoid the underbody or bumper grounding where the slope changes abruptly. Transitions ease the grade change at each end.
How do I calculate total ramp length?
Add the top transition, the main ramp run and the bottom transition. The tool solves the main run from the height left after the transitions and sums the lengths.
Is this AS/NZS 2890.1 compliant?
No. It's a calculation helper using generic grade profiles. AS/NZS 2890.1 is copyright and project/council specific — confirm with a traffic engineer or certifier.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.