ADA Parking Space Calculator

How the ADA parking space requirement is calculated

The federal 2010 ADA Standards for Accessible Design set a minimum number of accessible parking spaces based on the total number of spaces in a parking facility. This calculator applies that table directly. For the first several brackets the minimum steps up one space at a time: 1 accessible space is required for a lot of 1–25 spaces, 2 for 26–50, 3 for 51–75, 4 for 76–100, then 5 for 101–150, 6 for 151–200, 7 for 201–300, 8 for 301–400, and 9 for 401–500.

Above 500 spaces the rule shifts to a percentage: lots of 501 to 1,000 spaces require 2% of the total to be accessible, rounded up. For very large facilities over 1,000 spaces, the requirement is 20 spaces plus one additional space for every 100 (or fraction) over 1,000. The number shown in the big result above is that minimum accessible-space count for the total you entered.

Van-accessible spaces

Not every accessible space is the same. The ADA requires that at least one of every six accessible spaces — rounded up — be van-accessible, with a wider access aisle and signage that reads "van accessible." A lot with four accessible spaces needs one van-accessible space; a lot with seven needs two. When you leave the "include van-accessible breakdown" box checked, the calculator splits your total accessible count into standard and van-accessible spaces so you can plan the wider aisles and posts those spaces require. Van-accessible spaces are typically 11 feet wide with a 5-foot access aisle, or 8 feet wide with an 8-foot aisle, depending on the layout you choose.

Medical and outpatient facilities are different

The general table above is the baseline for most retail, office, and mixed-use lots. Medical facilities have higher requirements. Outpatient medical care facilities must generally provide accessible parking equal to 10% of patient and visitor spaces, and outpatient rehabilitation or physical therapy facilities that specialize in treating mobility conditions must provide 20%. When you check the "medical / outpatient facility" box, this tool flags that note in the assumptions, because the figure shown is the general minimum and your facility may owe more. Hospitals with outpatient units, dialysis centers, and rehab clinics should plan against the higher percentage and confirm the exact figure with their jurisdiction.

The ADA is a minimum, not the whole picture

Hitting the right count is only the start of an accessible layout. Each accessible space needs a level, properly graded surface (running and cross slopes no steeper than 1:48), an adjacent access aisle, an accessible route connecting it to the building entrance, and the correct signage mounted at the required height. Spaces also have to be dispersed so they serve the closest accessible entrances rather than being clustered in one far corner. Getting these details right is exactly what an ADA compliance striping crew handles, and it is why a paper count alone does not equal compliance.

Final compliance depends on federal ADA standards plus your state and local requirements — confirm with your jurisdiction and a contractor experienced in ADA layouts. Many states and cities adopt accessibility codes that meet or exceed the ADA, and separate lots on the same property are usually counted on their own rather than combined. For the full set of rules, read our ADA parking lot requirements guide, and when you are ready to price the work, the parking lot striping cost calculator covers the striping side of the project.

Using this number to plan your project

Once you know how many accessible and van-accessible spaces you need, you can lay out your stalls, order the right number of signs and posts, and budget for the access aisles that eat into your total stall count. If you are re-striping an existing lot, compare your current accessible-space count against this minimum — older lots are frequently short, especially on van-accessible spaces, which were not required in the same numbers under earlier standards. Bringing the lot up to the current ADA minimum during a routine re-stripe is far cheaper than addressing it after a complaint or inspection, and a contractor who works in ADA layouts every day can confirm the count, the dispersion, and the signage in a single visit.

These figures are national-average estimates for general guidance only. They are not a quote. Actual pricing depends on your location, the condition and size of your asphalt, prep work required, and the contractor. Request a free quote for an accurate price.