Parking Lot Layout Calculator How Many Spaces Fit.
Enter the lot's length and width. Every stall is drawn to scale, with the aisles, the striping footage and the ADA count.
Stall, aisle and drive lane sizes
The aisle starts at the SUDAS/ULI minimum for the angle; your city's code may allow less or require more. Cross lanes join the aisles at the lot's ends.
168 stalls fit, 6 rows of 28.
- Per stall, lot included
- 357 sq ft
- Stall striping
- 3,636 lin ft
- ADA minimum
- 6 (1 van)
3 aisles, 3 double-loaded modules. Striping counts one line per stall edge and the line between back-to-back rows; the accessible spaces come out of the same stalls, and islands, poles and entrances cost more.
Stalls and aisles from SUDAS Table 8B-1.02 (ULI and National Parking Association dimensions). A layout estimate for a clean rectangle, not a site plan: your city's code sets the minimums.
How Many Parking Spaces Fit in a 300 × 200 Lot
60,000 sq ft, 1.38 acres, with a 24 ft lane across each end. The angle alone moves the count by 22 stalls. Two-way angled rows do worse: 161 at 60°, 126 at 45°.
6 rows of 28, 357 sq ft of lot a stall.
8 rows of 23, 326 sq ft of lot a stall. The most on this lot.
9 rows of 18, 370 sq ft of lot a stall.
Run the Aisles the Long Way
Every aisle needs a lane at its ends to turn into, and those lanes hold no stalls. Aisles along the lot's long side mean fewer, longer rows, and fewer ends. The same lots, 90° stalls, turned one way and then the other:
| Lot | Long way | Short way | Gain |
|---|---|---|---|
| 300 × 200 ft | 168 | 160 | +5% |
| 400 × 250 ft | 312 | 264 | +18% |
| 300 × 120 ft | 112 | 80 | +40% |
How the Calculator Lays Out a Lot
The module geometry the SUDAS design manual draws, from the stall and aisle minimums on the parking space dimensions page.
One module at a time
A module is two rows of stalls and the aisle between them: 60' curb to curb at 90°, 51'6" at 60° and 47' at 45° on one-way aisles. The calculator stacks as many as the lot's width holds, then adds one row with its own aisle if the leftover fits a stall and an aisle.
Angled rows nest
Where two angled rows back onto each other, the stall tips interlock and the pair takes less width than two separate rows: the calculator takes the interlock off each shared edge, as SUDAS draws it.
Stalls along the row
Each stall takes its width along the curb at 90° (9 ft) and more when angled: 10'5" at 60°, 12'9" at 45°. An angled row also runs past its last stall by the slant of the line, so it needs a little extra length.
Lanes across the ends
A lane at each end ties the aisles together. The calculator makes it 24 ft, borrowed from the lot driveway SUDAS sizes for two-way traffic (two 12 ft lanes). Set it to one end or none when the aisles already open onto a drive or the street.
What comes out on a real lot
- Entrances. Rows should stop short of an entrance or exit, so cars pulling out of a stall do not meet cars turning in.
- Islands and poles. Landscape islands take the room of the stalls they replace; light poles may stand up to 2 ft into a module if they touch no more than 30% of the stalls.
- Accessible spaces. They replace standard stalls on the shortest accessible route to the building's accessible entrance, wider, and two may share an access aisle. The ADA parking calculator gives the count and the stalls they displace.
- Striping. The 300 × 200 lot at 90° is 3,636 linear feet of striping, stall lines and the lines between back-to-back rows, about 21.6 ft a stall. The striping cost estimator prices it.
Checked On A Real Lot.
The calculator's 90° module is 60' curb to curb. On a retail lot in Pineville, NC, measured straight down on 6-inch imagery, the bays repeat every 60', stalls are 8'6" wide, and stall lines run about 18', leaving about a 24' aisle.
SurfaceMeasure measures the whole lot from above: trace it on satellite, get the paved square footage, and send a branded quote your customer can accept online.
Parking Lot Layout Questions
Lay out rows of stalls around drive aisles and count them. With 9 × 18 ft stalls, 90° parking takes a 24' two-way aisle and 60' from curb to curb for two rows. A 300 × 200 ft lot with a 24 ft lane across each end fits 6 rows of 28: 168 stalls, about 357 sq ft of lot per stall. Islands, entrances and poles take some back.
22 at 90° if the aisle opens to the street or a drive at both ends: one 24' aisle down the middle with a row of 11 on each side. Add a 24 ft turnaround lane at one end and it drops to 16. The width left over (40 ft) is not enough for a third row and its own aisle.
Run the aisles along the lot's long side, then compare 90° two-way against 60° one-way: which wins depends on how the lot's width divides into modules. On a 300 × 200 ft lot, 60° one-way fits the most (184); 90° fits 168 and 45° one-way 162. Two-way angled rows waste aisle: on the same lot they fit 161 at 60° and 126 at 45°.
60' for two rows of 90° stalls facing each other across a two-way aisle: 18' of stall, 24' of aisle, 18' of stall. Angled parking on a one-way aisle needs 51'6" at 60° and 47' at 45°. A single row with its own aisle needs 42 ft at 90°.
Measure the lot's length and width, pick the angle and the aisle direction, then stack modules across the lot's width: two rows and an aisle, 60' each at 90°. Leave a lane across the ends so every aisle connects, end rows short of entrances, and check the accessible spaces against Table 208.2 before any paint goes down.
Yes: this calculator is free, with no sign-up. Enter the lot's length and width, pick 90°, 60° or 45° and the aisle direction, and it draws every stall to scale with the aisles, the cross lanes, the striping footage and the ADA minimum. It lays out a clean rectangle; islands, entrances and odd-shaped lots still need a site plan.
Count the stall lines: one more than the stalls in each row, each as long as the stall, plus the line between back-to-back rows. The 300 × 200 ft example at 90° takes 3,636 linear feet for 168 stalls, about 21.6 ft a stall; double (hairpin) lines about double the stall lines. Arrows, stop bars and accessible markings are extra.
It shows the minimum the 2010 ADA Standards require for the stalls it lays out: 6 accessible, 1 of them van accessible, for the 168-stall example. Accessible spaces are wider and two may share an access aisle, so they replace standard stalls rather than adding to them. The ADA parking calculator works out how many stalls they displace.
SUDAS tabulates 90° parking with a two-way aisle only, 24'; some local codes allow a slightly narrower one-way aisle at 90°. Angled stalls pair with one-way aisles: the aisle can be narrower and cars pull in with traffic. SUDAS allows two-way angled rows but says they take about 10 to 15% more pavement per stall than 90° or one-way angled rows.
Sources
Read September 2026. A first layout for bidding and planning, not a stamped site plan: the city's code and its reviewer have the last word.
- Iowa SUDAS Design Manual, Section 8B-1: Layout and Design (2013 edition)Table 8B-1.02 stall projections, aisles, modules and interlock (adapted from ULI and NPA); lot entrances, terminating rows, light poles, two-way angled parking.
- U.S. Department of Justice: 2010 ADA Standards for Accessible DesignTable 208.2, the minimum accessible and van accessible spaces the calculator shows.
- NC OneMap: statewide orthoimageryThe aerial of the Pineville, NC lot, 6-inch resolution, flown February 2023.