Data & Assets
Cities
The cities array contains ~270 major world cities, including every national capital. Each city has coordinates (lat/lon), country code, and population where available.
Live capital finder
Import
import {
cities,
getCitiesByCountry,
getCapitalCity,
getCitiesByPopulation,
searchCities,
} from "arevdata";
import type { City } from "arevdata";
Data shape
interface City {
name: string; // "Tokyo"
country: string; // ISO 3166-1 alpha-2, e.g. "JP"
state?: string; // State/region name (optional), e.g. "Tokyo"
population?: number; // Approximate city population (optional)
lat: number; // Latitude (−90 to 90)
lon: number; // Longitude (−180 to 180)
capital?: boolean; // true if this is the national capital
}
Examples
All cities
import { cities } from "arevdata";
console.log(cities.length); // ~270
// All national capitals
const capitals = cities.filter(c => c.capital);
console.log(capitals.length); // ~185
Capital city of a country
import { getCapitalCity } from "arevdata";
getCapitalCity("GB");
// { name: "London", country: "GB", lat: 51.5074, lon: -0.1278, capital: true, population: 9648110 }
getCapitalCity("JP");
// { name: "Tokyo", country: "JP", lat: 35.6762, lon: 139.6503, capital: true, population: 13960000 }
getCapitalCity("ZZ"); // undefined
Cities in a country
import { getCitiesByCountry } from "arevdata";
const usCities = getCitiesByCountry("US");
usCities.map(c => c.name);
// ["New York City", "Los Angeles", "Chicago", "Houston", "Phoenix",
// "Philadelphia", "San Antonio", "San Diego", "Dallas", "Washington D.C.", ...]
Top cities by population
import { getCitiesByPopulation } from "arevdata";
// Top 10 most populous cities
const top10 = getCitiesByPopulation(10);
top10.map(c => `${c.name} (${c.country})`);
// ["Chongqing (CN)", "Tokyo (JP)", "Delhi (IN)", "Shanghai (CN)", ...]
// All cities sorted by population
const all = getCitiesByPopulation();
Search cities by name
import { searchCities } from "arevdata";
searchCities("new");
// [{ name: "New York City", ... }, { name: "New Delhi", ... }, ...]
searchCities("london");
// [{ name: "London", country: "GB", ... }]
// Case-insensitive
searchCities("BERLIN"); // same as searchCities("berlin")
Build a city autocomplete
import { searchCities, getCountryByCode } from "arevdata";
function cityAutocomplete(input: string) {
return searchCities(input).map((city) => {
const country = getCountryByCode(city.country);
return {
label: `${city.name}, ${country?.name ?? city.country}`,
value: { lat: city.lat, lon: city.lon, code: city.country },
};
});
}
cityAutocomplete("par");
// [{ label: "Paris, France", value: { lat: 48.8566, lon: 2.3522, code: "FR" } }]
Calculate distance from capital to capital
import { getCapitalCity } from "arevdata";
import { haversineDistance } from "arevdata";
const amsterdam = getCapitalCity("NL")!;
const berlin = getCapitalCity("DE")!;
const km = haversineDistance(amsterdam.lat, amsterdam.lon, berlin.lat, berlin.lon);
// ~577 km
Coverage
Cities were chosen to cover:
- All national capitals (~185 cities)
- The largest metropolitan areas on each continent
- Major cultural, economic, and tourist destinations
Cities from every continent are represented including remote capitals like Nuku’alofa (Tonga), Funafuti (Tuvalu), and Majuro (Marshall Islands).