A cluster is the numbered bubble that stands in for several listings sitting close together on the map. Click it and the map zooms in, the group breaks apart, and the individual price pins appear.
Clustering is on by default and controlled by two settings on the Maps tab of MLS Import Design Settings: Use the Pin Cluster on the maps and Maximum zoom level for cluster to appear.
Why the map clusters at all
A search over a whole county can match thousands of listings. Drawing thousands of pins would send every one of them to the browser and produce a map nobody can read, since the pins would cover each other.
Clustering solves both problems at once. The map asks the server for what is inside the current view, the server groups anything too close together to distinguish, and the browser receives a short list of bubbles and pins instead of the whole feed.
How the grouping is decided
The map is divided into square cells roughly seventy pixels across at the current zoom. Every listing in view falls into one cell.
- A cell holding one listing is drawn as that listing’s price pin, with its photo card on click.
- A cell holding two or more is drawn as a bubble showing the count.
Because the cells are measured in screen pixels, zooming in makes each cell cover less ground. Listings that shared a cell stop sharing one, and the bubble splits into smaller bubbles and then into pins. That is why the same map shows one bubble of 400 at region level and a scatter of individual pins at street level.
A single listing standing alone always renders as a pin, at any zoom. If you see one lone pin far from everything else while the rest of your market is a bubble, that pin is worth investigating rather than admiring. It usually means a listing with wrong coordinates.
The two settings
Use the Pin Cluster on the maps is the master switch. Set it to No and nothing ever groups: every listing in view is drawn as its own pin at every zoom level.
Maximum zoom level for cluster to appear is the cut-over, and the default is 11. Clusters appear up to and including that level, and from one level further in every listing is a separate pin. The boundary is inclusive, so 11 means bubbles at zoom 11 and pins at zoom 12.
Raise it to keep grouping further in, which suits a dense urban market where pins still overlap at street level. Lower it to break groups apart sooner, which suits a rural market with listings far apart.
Turning clustering off looks tidier on a demo site with fifty listings and behaves badly on a real one. With it off, a visitor who zooms out to the state gets every matching listing drawn as an individual marker, which is exactly the load clustering exists to avoid.
Reading a bubble
The number is how many listings are inside it. Counts of a thousand and over are shortened, so 4,928 appears as 4.9k, and the bubble grows through three sizes as the count rises.
Clicking a bubble zooms in two levels and recentres on it. Two clicks from a regional view usually gets you to individual listings.
Where clustering applies
Clustering belongs to maps that draw a filtered set of listings, which means the Map with Listings block in filter mode and the map half of the Half Map block. Panning or zooming either one refetches the listings for the new view.
A Map with Listings block set to a hand-picked list of properties never clusters. That set is small and fixed, so every chosen listing is drawn as its own pin and the map fits itself to them.
In the supported themes the map is drawn by the theme, and so is any clustering it does. These settings do not reach it.
Frequently asked questions
Does the map load all my listings into the visitor’s browser?
No. It requests only what is inside the current view, and it requests again after a pan or a zoom. The size of your database does not change how much the map sends.
Why does the count on a bubble change when I pan the map?
Because it counts what is in view. Panning changes the view, the server recalculates, and the same area can regroup differently once new listings enter the edge of the map.
I have a bubble that will not split no matter how far I zoom in. Why?
Several listings share one coordinate. That is normal for a condo building where every unit carries the address’s coordinates, and it is a warning sign when the bubble sits somewhere no building exists.
Do clusters work the same in Live Mode?
The idea is the same and the source is not. Live Mode has no local table to group, so wide views are answered with counts from an index refreshed daily, and a map with filters applied asks the visitor to zoom in instead.
Related
- Setting up the map: MapBox key, starting point and zoom
- Why some properties appear in the ocean
- The Half Map block
- The Map with Listings block
- Live Mode limitations
Tell us your market and how your pins behave today and we will suggest a cut-over zoom.