API Documentation

Complete reference for the GeoData API.

Quick Links

Authentication →
Single Lookup →
Batch Lookup →
Data Categories →
Error Codes →

Authentication

All API requests require an API key passed in the X-API-Key request header:

X-API-Key: YOUR_API_KEY

Single Lookup

Get data for a single GB postcode:

GET /v1/lookup?location=SW1A1AA&categories=demographics,housing

Parameters

location - GB postcode (required)
categories - Comma-separated list (optional)

Code Examples

curl -X GET "https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics" \
  -H "X-API-Key: YOUR_API_KEY"

const response = await fetch(
  "https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics",
  {
    headers: {
      "X-API-Key": "YOUR_API_KEY",
    },
  }
);

const data = await response.json();
console.log("Population:", data.results.demographics.population.total);

import requests

response = requests.get(
    "https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics",
    headers={"X-API-Key": "YOUR_API_KEY"},
)

data = response.json()
print("Population:", data["results"]["demographics"]["population"]["total"])

require "net/http"
require "json"

uri = URI("https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics")
request = Net::HTTP::Get.new(uri)
request["X-API-Key"] = "YOUR_API_KEY"

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) do |http|
  http.request(request)
end

data = JSON.parse(response.body)
puts "Population: #{data["results"]["demographics"]["population"]["total"]}"

$ch = curl_init("https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics");

curl_setopt($ch, CURLOPT_HTTPHEADER, [
    "X-API-Key: YOUR_API_KEY",
]);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

$response = curl_exec($ch);
curl_close($ch);

$data = json_decode($response, true);
echo "Population: " . $data["results"]["demographics"]["population"]["total"];

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-API-Key", "YOUR_API_KEY");

var response = await client.GetStringAsync(
    "https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics"
);

var data = JsonDocument.Parse(response);
var population = data.RootElement
    .GetProperty("results")
    .GetProperty("demographics")
    .GetProperty("population")
    .GetProperty("total");
Console.WriteLine($"Population: {population}");

req, _ := http.NewRequest("GET",
    "https://geodata.api.leadinglogic.ai/v1/lookup?location=SW1A1AA&categories=demographics", nil)
req.Header.Set("X-API-Key", "YOUR_API_KEY")

resp, _ := http.DefaultClient.Do(req)
defer resp.Body.Close()

var result map[string]interface{}
json.NewDecoder(resp.Body).Decode(&result)
fmt.Println("Status:", resp.Status)

Batch Lookup

Get data for multiple postcodes (max 100):

POST /v1/batch
Content-Type: application/json

{
  "locations": ["SW1A1AA", "M11AD"],
  "categories": ["demographics"]
}

Code Examples

curl -X POST "https://geodata.api.leadinglogic.ai/v1/batch" \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "locations": ["SW1A1AA", "M11AD"],
    "categories": ["demographics"]
  }'

const response = await fetch(
  "https://geodata.api.leadinglogic.ai/v1/batch",
  {
    method: "POST",
    headers: {
      "X-API-Key": "YOUR_API_KEY",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      locations: ["SW1A1AA", "M11AD"],
      categories: ["demographics"],
    }),
  }
);

const data = await response.json();
console.log("Results:", data.results);

import requests

response = requests.post(
    "https://geodata.api.leadinglogic.ai/v1/batch",
    headers={"X-API-Key": "YOUR_API_KEY"},
    json={
        "locations": ["SW1A1AA", "M11AD"],
        "categories": ["demographics"],
    },
)

data = response.json()
for result in data["results"]:
    print(result["location"], result["demographics"]["population"]["total"])

require "net/http"
require "json"

uri = URI("https://geodata.api.leadinglogic.ai/v1/batch")
request = Net::HTTP::Post.new(uri)
request["X-API-Key"] = "YOUR_API_KEY"
request["Content-Type"] = "application/json"
request.body = {
  locations: ["SW1A1AA", "M11AD"],
  categories: ["demographics"]
}.to_json

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) do |http|
  http.request(request)
end

data = JSON.parse(response.body)
data["results"].each { |r| puts r["location"] }

$ch = curl_init("https://geodata.api.leadinglogic.ai/v1/batch");

curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    "X-API-Key: YOUR_API_KEY",
    "Content-Type: application/json",
]);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
    "locations" => ["SW1A1AA", "M11AD"],
    "categories" => ["demographics"],
]));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

$response = curl_exec($ch);
curl_close($ch);

$data = json_decode($response, true);
foreach ($data["results"] as $result) {
    echo $result["location"] . "\n";
}

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-API-Key", "YOUR_API_KEY");

var payload = new {
    locations = new[] { "SW1A1AA", "M11AD" },
    categories = new[] { "demographics" }
};

var content = new StringContent(
    JsonSerializer.Serialize(payload),
    Encoding.UTF8, "application/json"
);

var response = await client.PostAsync("https://geodata.api.leadinglogic.ai/v1/batch", content);
var json = await response.Content.ReadAsStringAsync();

var data = JsonDocument.Parse(json);
Console.WriteLine(data.RootElement.GetProperty("results"));

body := bytes.NewBufferString(`{
  "locations": ["SW1A1AA", "M11AD"],
  "categories": ["demographics"]
}`)

req, _ := http.NewRequest("POST", "https://geodata.api.leadinglogic.ai/v1/batch", body)
req.Header.Set("X-API-Key", "YOUR_API_KEY")
req.Header.Set("Content-Type", "application/json")

resp, _ := http.DefaultClient.Do(req)
defer resp.Body.Close()

var result map[string]interface{}
json.NewDecoder(resp.Body).Decode(&result)
fmt.Println("Results:", result["results"])

Data Categories

demographics - Population, age, ethnicity (Census 2021)
economic - Employment, economic activity (ONS / NRS)
housing - Property prices, tenure (Land Registry)
crime - Crime statistics (Police UK)
business - Enterprise counts (ONS)
deprivation - IMD scores (MHCLG)
education - Nearest schools (DfE / gov.scot)
connectivity - Broadband & mobile coverage (Ofcom)
energy - EPC energy efficiency ratings (MHCLG / Scottish Government)
flood - Rivers & sea flood-risk bands (Environment Agency)
health-conditions - Modelled GP long-term condition prevalence for England (21 NHS England QOF conditions), Wales (StatsWales GP disease registers) and Scotland (Public Health Scotland GP disease prevalence). Each location is compared with its own nation's rate (national, vsNational, nation). Wales and Scotland publish no practice-to-area patient split, so their estimates are modelled from practice locations (method: "modelled-distance"). Condition sets and age groups differ by nation; population gives each rate's age group.
climate - Observed climate on a 1 km grid (Met Office HadUK-Grid): temperature, rainfall, sunshine and frost for the latest year and each season, with the 1991–2020 average

Error Codes

400 - Invalid request
401 - Missing or invalid API key
403 - Category not available on your plan
404 - Location not found
429 - Rate limit exceeded