How HDB's live carpark availability works
Figures checked 4 November 2026
Every number on the Where to Park@SG map starts at the carpark itself. This guide follows a lot count from the carpark to your screen, and explains what to make of gaps and odd numbers along the way.
From the carpark to your phone
- Each HDB carpark's parking system keeps count of the lots in use.
- HDB collects these counts and publishes them as an open dataset on data.gov.sg, the Singapore Government's open data portal.
- Where to Park@SG reads that dataset every minute and keeps a compact copy, so your phone downloads a small file instead of the full dataset.
- The app matches each count to the carpark's location and name, from HDB's separate Carpark Information dataset, and puts it on the map.
Each carpark reports on its own schedule. When we checked, half of all carparks had sent a new count in the previous two minutes. The List tab shows when the counts were last updated.
How many carparks report live numbers
HDB lists 2,273 carparks. About half are multi-storey (1,132) and almost as many are surface carparks (1,071), with a few dozen basement, covered and mechanised ones. Of these, about 2,000 send live lot counts. The rest, around 270, appear on the map with "No data".
Counts are kept separately for each kind of lot:
- Car lots: reported by every carpark that sends live data.
- Motorcycle lots: reported by about 210 carparks.
- Heavy-vehicle lots (lorries, buses and similar): also about 210 carparks.
A carpark may have motorcycle or heavy-vehicle lots that aren't counted live. The app only shows the counts it receives, so in motorcycle or heavy-vehicle mode those carparks don't appear.
Why a carpark shows "No data"
- It doesn't send live counts. Its location is known from HDB's carpark list, but no lot numbers arrive for it.
- Its numbers have stopped updating. Sometimes a carpark keeps appearing in the dataset with the same count for days. Where to Park@SG treats any count more than 24 hours old as unreliable and shows "No data" rather than a stale number.
Why the count can differ from what you find
- Time: a lot shown as free a few minutes ago may have been taken while you were on the way.
- Counting: the numbers come from the carpark's own system. If a gantry or sensor misses a vehicle, the count is off until it's corrected.
- Lots you can't use: some lots may be reserved, for example for season parking holders, or closed for works.
Treat the numbers as a strong hint rather than a guarantee, and see tips for finding a free lot for ways to allow for this.
Small quirks we handle for you
About a dozen carparks appear twice in HDB's dataset, each time with a different kind of lot (say, cars in one record and motorcycles in the other). The app combines them so you see one carpark with all its lot counts.
Contains information from HDB Carpark Information and Carpark Availability accessed from data.gov.sg, which is made available under the terms of the Singapore Open Data Licence version 1.0.