I built a zero-dependency city search library with 50,000 cities built-in

Most geo projects need city search, distance calculation, or nearest location logic at some point. The usual answer is "hit a third-party API." But that means latency, rate limits, API keys, and cost.

I built @novaedgedigitallabs/citykit to solve this — a zero-dependency utility library that ships with a full dataset of 49,992 cities across 242 countries, ready to use offline.

Install

npm install @novaedgedigitallabs/citykit

No API key. No setup. Works in Node.js and TypeScript out of the box.

What it can do

1. Search cities

import { search } from '@novaedgedigitallabs/citykit';

const results = search('Mumbai');
console.log(results);
// [{ name: 'Mumbai', country: 'IN', lat: 19.0760, lng: 72.8777, ... }]

Fuzzy-friendly, returns ranked matches.

2. Calculate distance between two cities (Haversine)

import { distance } from '@novaedgedigitallabs/citykit';

const km = distance(
  { lat: 22.7196, lng: 75.8577 }, // Indore
  { lat: 19.0760, lng: 72.8777 }  // Mumbai
);

console.log(km); // ~590 km

Uses the Haversine formula — accurate great-circle distance, no API needed.

3. Find nearest cities to a location

import { nearest } from '@novaedgedigitallabs/citykit';

const cities = nearest({ lat: 22.7196, lng: 75.8577 }, 5);
// Returns 5 closest cities to Indore

Great for "cities near me" features.

4. Filter by country, state, or continent

import { filterByCountry, filterByContinent } from '@novaedgedigitallabs/citykit';

const indianCities = filterByCountry('IN');
const europeanCities = filterByContinent('EU');

5. Country and capital data

import { getCountry, getCapital } from '@novaedgedigitallabs/citykit';

getCountry('IN');   // { name: 'India', code: 'IN', continent: 'AS', ... }
getCapital('IN');   // 'New Delhi'

Why zero dependencies?

Most libraries in this space pull in heavy geo packages or call external APIs. citykit bundles the dataset directly — the tradeoff is a slightly larger install size, but you get:

Works fully offline
No rate limits
No API keys to manage
No latency from network calls
Predictable behavior in serverless / edge environments

There's also a lightweight variant if you only need basic search without the full dataset.

Real use cases I've used it for

Autocomplete city input on a form (no API call on every keystroke)
Distance filter for a property listing platform
"Nearest branch" feature for a business directory
Seeding a database with city/country data

15 functions, one import

The full list: search, distance, nearest, filterByCountry, filterByState, filterByContinent, filterByRadius, getCountry, getCapital, getAllCountries, getCitiesByPopulation, getCity, getContinents, listCountries, lightSearch