is-it-bst

From gov.uk:

In the UK the clocks go forward 1 hour at 1am on the last Sunday in March, and back 1 hour at 2am on the last Sunday in October.

isItBST(date) works it out for you.

install

$ npm install is-it-bst

Works fine in the browser using Browserify.

use

var isItBST = require('is-it-bst');
 
isItBST(new Date('2014-07-1')); // true
 
isItBST(new Date('2014-12-1')); // false
 
isItBST(); // true/false based on the current date