Transparency & Attribution
Data & Sources
Learn where the information used by HDB Resale Portal comes from, how official datasets are processed, and the limitations to consider when interpreting results.
Overview
Official data with independent analysis
HDB Resale Portal combines three official Housing & Development Board datasets with OneMap mapping services and the portal's own data-processing and spatial-analysis logic.
HDB Dataset
Resale Transaction Data
Resale transaction information displayed by the portal comes from the official HDB resale price dataset published through data.gov.sg.
- Agency
- Housing & Development Board (HDB)
- Dataset ID
- d_8b84c4ee58e3cfc0ece0d773c8ca6abc
- Format used
- CSV
- Portal usage
- Transaction month, town, flat type, block, street, storey range, floor area, flat model, lease information and resale price.
HDB states that transactions which may not reflect full market price, including certain transactions between relatives or part-share transactions, may be excluded. Resale prices should therefore be treated as indicative rather than as formal valuations.
HDB Dataset
HDB Existing Building
The portal uses the HDB Existing Building geospatial dataset to understand where individual HDB blocks are located.
- Agency
- Housing & Development Board (HDB)
- Dataset ID
- d_16b157c52ed637edd6ba1232e026258d
- Format used
- GeoJSON
- Portal usage
- Block number, street code, postal code and building polygon geometry.
Building geometry is stored in PostgreSQL using PostGIS and is used to identify HDB blocks that fall within the selected search radius.
HDB Dataset
HDB Property Information
HDB Property Information provides reference information about HDB blocks.
- Agency
- Housing & Development Board (HDB)
- Dataset ID
- d_17f5382f26140b1fdae0ba2ef6239d2f
- Format used
- CSV
- Portal usage
- Used to associate human-readable street names with HDB building records.
Postal codes displayed by HDB Resale Portal come from the HDB Existing Building dataset, not from HDB Property Information.
Licensing
Singapore Open Data Licence
The HDB datasets used by this portal are made available through data.gov.sg under the Singapore Open Data Licence.
Contains information from Housing & Development Board datasets accessed through data.gov.sg and made available under the Singapore Open Data Licence.
Mapping
OneMap
The interactive Explorer uses the OneMap basemap provided by the Singapore Land Authority.
OneMap is used for the interactive basemap and to resolve selected HDB addresses to postal codes for nearby searches.
HDB resale transactions, property information and building geometry continue to come from the HDB datasets described above.
Methodology
How the portal processes data
The portal performs its own processing after retrieving the source datasets.
Official resale data is retrieved from data.gov.sg.
Values are normalised and remaining lease information is converted into months for easier calculation.
Resale transactions are matched to HDB buildings using block and street information.
PostGIS performs radius searches against HDB building geometry.
Transaction count, median, lowest and highest prices are calculated from matching transactions.
Results are displayed through maps, transaction lists and block-detail views.
Important Information
Data limitations
- Historical resale prices are not formal property valuations.
- Sale prices may be affected by storey, renovation, orientation, condition, remaining lease and other property-specific factors.
- Certain transactions may be excluded from the source HDB dataset where they may not reflect full market price.
- Building-to-transaction matching depends on consistent block and street information across different datasets.
- Nearby searches depend on available building geometry and postal-code information.
- Historical statistics do not predict future sale prices.
- Loan Calculator results are estimates and do not constitute financial advice or a loan offer.
Technology
Software used by the portal
Independence
Independent project
HDB Resale Portal is an independent project. It is not operated by, affiliated with, sponsored by or endorsed by the Housing & Development Board, Singapore Land Authority, GovTech Singapore or the Singapore Government.
Government datasets, organisation names and services referenced on this website remain subject to the terms and conditions of their respective owners and providers.