Method

How Locate Flock works

Every camera on this site is a point that a volunteer added to OpenStreetMap. This page sets out where those points come from, how each figure on a place page is worked out, and where the data falls short.

The data right now

Data built on: October 2, 2026
OpenStreetMap as of: October 1, 2026 at 21:04 UTC
Cameras mapped: at least 143,570
Refreshed: once a week

Quoting a figure? Give the data date shown on the page you took it from. The numbers move as volunteers add and correct pins.

Where the pins come from

Each pin is a node in OpenStreetMap (OSM), the free map of the world that anyone can edit. We take the nodes that carry the tag surveillance:type=ALPR. ALPR is short for automatic license plate reader: a camera, plus software, that reads the plates of passing vehicles.

Volunteers add these nodes, and can note more than the location: who made the camera, who runs it, which way it points. We read all of it with the Overpass API, a public service for querying OSM, asking for every node with that tag inside the United States.

The data is refreshed once a week. Each reply from Overpass states the moment its copy of OSM was current, and we publish that time with the data: it is the “OpenStreetMap as of” line above. An update is thrown out, and the previous one stays up, if the reply was built from older map data than the site already shows, or if the national count or a large state’s count has swung further than ordinary mapping would explain.

The maker comes from the node’s manufacturer tag, or brand where that is missing. Spellings are grouped into Flock Safety, Motorola Solutions (which includes Vigilant), Genetec, Leonardo (ELSAG), Neology (PIPS), other makers, and no maker recorded. On this site “Flock” always means a camera whose recorded maker is Flock Safety, and one with no maker recorded is never counted as Flock. In the current data, 115,332 of 143,570 mapped cameras are recorded as Flock Safety and 6,766 have no maker recorded.

What “mapped” means

“Mapped” means one thing here: somebody has added the camera to OpenStreetMap. It does not mean we have confirmed it, that it is switched on, or that it is still there.

So every count on this site is a minimum. A camera nobody has added is simply absent, so the true number in a place is whatever is mapped or more. A town with few pins may have few cameras, or few people mapping them, and the data cannot tell you which.

A pin can also be wrong. It may sit some way from the real pole, describe a camera that has since been taken down, be some other kind of camera mistaken for a plate reader, or name the wrong maker. Nobody at Locate Flock visits the cameras, and this site keeps no edited copy of its own: what you see is what is in OpenStreetMap. If you spot a mistake, corrections says how it gets fixed.

Places, boundaries and population

A “place” here is a place as the U.S. Census Bureau draws it: an incorporated city, town or village, or a census-designated place, which is a named community with no municipal government of its own. The outlines are the Bureau’s cartographic boundary files for places, 2025 edition, at 1:500,000 scale.

Two limits come with those outlines. The Bureau describes them as simplified shapes made for drawing maps, not for exact area calculations, so every share of a place’s area on this site is an approximation. And an outline takes in any water inside a place’s limits: for a place on a bay or a large lake, part of the area being measured is water, which makes its nearest camera look farther away than it is on land.

A camera belongs to a place when its point falls inside that outline. Plenty of cameras stand outside every outline. They count toward their state and appear on the map, but no place page includes them. In the current data, 73% of mapped cameras are inside an incorporated city, town or village. 79 of the 143,570 count toward no state, and so toward no place either: they sit just past a coast or a border as the simplified state outlines draw it, or in a territory without a row of its own, such as the U.S. Virgin Islands. They are still in the national total and on the map.

Population is the 2020 Census count of residents for the same place (table P1, total population). It is the latest full count, and it is used for one figure only: cameras per 10,000 residents.

How each figure is measured

Each place page carries the same set of figures, worked out the same way for every place. All distances are straight lines, measured in metres and rounded to the nearest 10.

Typical distance to the nearest camera

We lay a regular grid of sample points across the area inside the place’s outline. For each point we measure the distance to the nearest mapped camera of any make. That camera does not have to be inside the outline: one just over the town line still counts as near.

Two numbers sum up the resulting list of distances. The typical distance is the median: half of the sample points are closer to a camera than that, half are farther. The second figure, the 90th percentile, is the distance that nine points in ten are within. Each place page says how many sample points it used and how far apart they are.

Area close to a camera

From the same grid we work out what share of the area inside the outline lies within 400 metres of a mapped camera (about a quarter of a mile) and within 800 metres (about half a mile). The shares are whole percentages.

This is a measure of proximity and nothing more. It says how much of a place is near a pin. It says nothing about what any camera can see, which way it points or what it records.

Spacing between cameras

For every camera in a place we take the distance to the nearest other camera in the same place, then report the median of those distances, with the 25th and 75th percentiles to show the spread. The figure needs at least two mapped cameras.

Cameras that share a spot

A camera is counted as sharing a spot when another mapped camera stands within 60 metres of it. That is usually two cameras on one pole, or a group at one intersection.

Recorded direction

A mapper can record the compass bearing a camera points along, in the camera:direction tag or the plain direction tag. We sort the recorded bearings into eight compass sectors: north, north-east and so on round the dial. A camera recorded with two bearings is counted in two sectors.

An exact 0 gets special handling. Zero means due north, but it is also the value a camera is often left with when nobody set a bearing at all. Mappers tend to round bearings to the nearest ten, so we compare how often an exact 0 turns up with how often the other multiples of ten do. When zero is far more common than they are, we treat exact zeros as not recorded and keep them out of the direction figures. Nationwide, 130,627 of 143,570 mapped cameras count as having a recorded direction. The 7,295 tagged with an exact 0 are left out of that figure.

A recorded direction is what a mapper observed. It is not a statement of what the camera captures.

Who is recorded as running a camera

The operator tag names whoever runs a camera, in the mapper’s own words. We sort those names into five kinds:

Public agency: police and sheriff’s departments, transport departments, schools and other units of government.
Private: a business, a homeowners’ association or another private owner, and only when the name says so plainly.
Camera company: the name is that of a camera maker or reseller.
Other: a name the rules cannot place.
Not recorded: no operator tag, or filler such as “unknown”.

The rules lean towards saying less. A name counts as private only when it carries a clear commercial marker, a bare town name counts as an agency only inside its own state, and anything unclear goes to “other” instead of a guess.

Nationwide, 120,191 of 143,570 mapped cameras (84%) have no usable operator name. Read any split by operator as a description of the cameras that carry the tag, not of all of them.

Cameras per 10,000 residents

The number of mapped cameras inside the outline, divided by the place’s 2020 Census population and multiplied by 10,000. It is a floor like every other count here, and it is left out where there is no 2020 count for the place.

Which places get their own page

Every mapped camera is on the map and counts in a search near an address, wherever it stands. A page for a place is a higher bar, because a page built on a handful of pins would say little and its figures would jump with every edit.

A place is measured at all once 10 cameras are mapped inside its outline. In the current data that is 2,395 places, out of 8,855 with any mapped camera.
It qualifies for its own page once 40 cameras are mapped there.
In each state, the 2 places with the most mapped cameras qualify at a lower bar of 25, so that every state page has somewhere to send you.
A state gets a page when one of its places has one, or when 100 cameras are mapped in the state.

The site is new and adds place pages in stages. For now there are at most 330 of them. When more places qualify than there is room for, the ones let in first are those where a camera is typically closest. Later stages are set to lower the bar to 30 and then 20 mapped cameras.

A place that has a page keeps it: a larger newcomer never pushes it out. The page is withdrawn only if the place’s own count falls below 80% of the bar it came in on and stays there for 7 days. It is then kept for 60 more days, marked as not for search engines, before it is taken down, and it returns if the count recovers.

What this site will not do

It will not help anyone get around a camera. There is no advice here on avoiding, blocking or defeating plate readers, and no tool that plans a route past them.
It will not tell you what a camera recorded, whether it is working, or who can search its records. The data holds locations and a few tags, and that is all.
It will not look up a license plate or a person.

Some pages mention state laws and local rules about plate cameras. That is general information, and it is not legal advice.

Corrections

The pins belong to OpenStreetMap, so that is where a wrong one gets fixed. Nothing is corrected in a private copy here.

Open the camera on the map. Its panel links to that camera’s entry in OpenStreetMap.
Sign in to OpenStreetMap (an account is free) and move the node or fix its tags. If the camera has been taken down, mark it the way OpenStreetMap asks for things that no longer exist; our step-by-step guide shows how. A camera that is missing is added the same way: a new node that carries the tag surveillance:type=ALPR.
Change only what you have seen for yourself.
Your edit shows up here after the next refresh of the data, which runs once a week.

If you would rather not edit the map, tell us through the contact page: give the address or the coordinates, and say what is wrong.

A mistake in our own words or sums, as opposed to a pin, is ours to fix. Write to us and say which page it is on.

Glossary

ALPR: Automatic license plate reader: a camera with software that reads the plates of passing vehicles. Also written LPR.
Flock: On this site, a camera built by Flock Safety and nothing else. Cameras from other makers are named for their makers.
Mapped: Added to OpenStreetMap by a volunteer. Not the same as confirmed, and not the same as still standing.
Pin: One mapped camera: a single node in OpenStreetMap.
OpenStreetMap (OSM): The free, editable map of the world that every pin comes from.
Overpass: The public query service we use to read the pins out of OpenStreetMap.
Place: A city, town, village or census-designated place, with the outline the Census Bureau publishes for it.
Census-designated place: A named community that the Census Bureau outlines for statistics and that has no municipal government of its own.
Median: The middle value of a set of measurements: half are smaller, half are larger. A “typical” distance on this site is a median.
90th percentile: The value that nine measurements in ten do not exceed.
Proximity: How much of a place’s area lies within a set distance of a mapped camera. A matter of distance, not of what a camera sees.
Spacing: The distance from one camera to the nearest other mapped camera.
Operator: Whoever is recorded as running a camera.