About this service
Explore property boundaries, buildings and surroundings across Finland. Search by address or property identifier and measure distances and areas.
Tonttikartta collates and combines data from several open sources and synthesises it into one summary per property. People use the summaries on the map and the property pages; AI assistants use them through the API, the MCP server and llms.txt.
Scale
- 2.9m properties
- 3.8m land parcels
- 3.8m buildings
- about 47.7m map features
- 11 data providers
- 1.8m property pages
- 360k address pages
As of 28 October 2026. Figures are rounded and describe the data in this release. Tonttikartta is not an official register.
Tonttikartta is provided by OPL Consulting Oy.
What can I do now?
- Search by address, place, property identifier or coordinates.
- Property boundaries, basic information and building information where available.
- Map layers for the environment, forests, soil, cultural heritage and neighbourhoods.
- Planning and decision information with source documents in covered areas.
- Distance and area measurements, 3D terrain and indicative sunlight tools.
- Share a map link, print a Tonttikortti and use the service in Finnish or English.
Availability varies by location and source. Some layers appear only when you zoom in.
Built with the Maasto engine
Our proprietary Maasto engine renders the maps and supports rapid prototyping and AI agent integration.
Contact and corrections
Questions, feedback or a verifiable data mismatch? Contact us by email. Please include enough detail for us to find the location and reproduce the issue.
Service and Maasto engine copyright. Public-source data remains subject to its providers’ rights and licences.
Beta · This experimental service may contain errors or interruptions. Verify important details with the original provider.