Uptime check

Checks uptime status of given url and provided keyword (optional).

How it works

Makes simple fetch requests, gathers data on response and if requested also is looking for a keyword inside the document body.

If http code (response) is 2xx website is considered "up". If there is a keyword given for search, but the keyword cannot be found in the document body, website is considered "down".

v5 migration

From version 5 this package becomes 0-depencency. With that got got replaced with native fetch.

For the sake of maintenance ease, node@24 or higher is required.

To migrate please check the new function signature and returned result:

declare module "uptime-check" {
  export interface UptimeCheckResult {
    success: boolean; // true if test passed, false if failed
    statusCode: number;
    didRedirect: boolean;
    effectiveUrl: string; // last url in the redirects chain
    totalTime: number; // total request time
    thrownError?: Error; // in case of fetch error, original Error object
    thrownErrorCode?: string; // in case of a request error, e.g. ETIMEDOUT, CERT_HAS_EXPIRED, when provided
  }

  export interface UptimeCheckOptions {
    url: string;
    keyword?: string; // defaults to null
    allowRedirects: boolean; // defaults to false
    headers?: object;
  }

  export default function check(o: UptimeCheckOptions): Promise<UptimeCheckResult>;
}

v4 migration

From version 4 there is no userAgent option any more. If you used this, please migrate to:

check({
  headers: {
      'User-Agent': 'Your custom UA string',
  }
});

Example usage

import check from 'uptime-check';
const result = await check({
  url: 'https://example.com',
  keyword: 'Example',
  allowRedirects: true,
});

const isUp = result.success; // true or false