Tip: a postcode or full address both work. The finer the detail, the more elevation samples are pulled (a little slower). Click two points on the map afterwards to draw a cross-section.
Topographical plan
Site features (OpenStreetMap)
Planning & flood constraints
Cross-section / long profile
Site data
Status
Awaiting search
Elevation legend
Run a survey to populate.
Planning & flood constraints
Run a survey to check flood zones, conservation areas and listed buildings (England).
Survey notes
Datum, contour interval and source resolution will appear here once a survey is run.
What this tool is — and isn't
Is: a desktop topographical appraisal — the kind a developer/architect uses to understand a site's fall, slope, aspect and features before commissioning a measured survey.
Isn't: a substitute for a measured topographical survey by a chartered surveyor. Do not set out, design levels or build from this.
Heights are above Ordnance Datum (mASL), interpolated from open national elevation models.
Desktop study — not a measured survey. In England this now pulls the Environment Agency
1 m LiDAR Composite DTM live — near survey-grade ground modelling (≈0.15 m typical vertical
accuracy), the same source professional ground models use. Outside England (Scotland/Wales) or where
LiDAR is missing, it falls back to open national terrain (≈30 m, smoothed) — still good for overall
shape, fall and aspect. Heights are above Ordnance Datum (Newlyn). The DTM is bare-earth (below-canopy
ground, to LiDAR penetration), and the tool also derives surface-water flow paths & ponding from it,
shows the registered title boundary (HM Land Registry INSPIRE) and any OSM drains/manholes.
What it still cannot give — and a measured survey must — is cm-accurate spot/kerb/floor levels,
underground drainage runs & invert levels, and the determined (precise) legal boundary. Don't set out,
design levels or build from this; for design or a planning submission, commission a measured topographical survey.
AXO Consulting · Closed Beta
Datum
Instant topographical & site-constraints studies from open data. This is a private evaluation build — please don't share the link or outputs outside the test.