2017-11-27
2162
#vanilla javascript
Christian Nwamba
1821
Nov 27, 2017 ⋅ 7 min read

Detect location and local time zone of users in JavaScript

Christian Nwamba JS preacher. Developer 🥑. Building the web with the community @concatenateConf @forLoopAfrica. JS and Senior Advocacy for the Next Billion Users through Microsoft.

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5 Replies to "Detect location and local time zone of users in JavaScript"

  1. thank you for the post! Just realised that you mixed up longitude and latitude in the reverseGeocodingWithGoogle function 😉

  2. Interesting post! I have one query related to DST. Is there any way in Javascript which will give us user’s tzid and tz long name based on tz database used in Joda library? These tzids are widely used universally and are defined by IANA database. Java’s Joda Library also use the same tz database.

    Joda library gives different DST data (not shown below) for same offset i.e. +04:00…like as below:

    (+04:00) Europe/Ulyanovsk, Greenwich Mean Time
    (+04:00) Europe/Volgograd, Moscow Standard Time
    (+04:00) Indian/Mahe, Seychelles Time
    (+04:00) Indian/Mauritius, Mauritius Time
    (+04:00) Indian/Reunion, Reunion Time

    we have to apply those DST rules while sending icalendar file (ICS files) to users. Users are located at different regions.

    if user’s timezone detected by JS is “+04:00 with some country”, then how can we decide which DST rule out of several should be applied? Because I dont have any country to region mapping.

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