Indian Standard Time - IST is Five and a Half hours ahead of UTC / GMT. India has no Daylight Saving Time (DST) although the country spans more than 2000 Km East to West. Some of the North eastern states have a different 'Tea Garden Time' to save Daylight. IST is defined as the local time at 82.5° E longitude, passing through Mirzapur near Allahabad in Uttarpradesh. The 5:30 hours difference with London Time (GMT) gives rise to a curious phenomenon for the British tourist. If you flip your analog clock and read the time off, you will get the current IST from a watch showing GMT.
All India Radio, Doordarshan the Government TV channel announce the time at regular intervals.