The Pips: The Greenwich Time Signal Explained
The pips are the short beeps broadcast on BBC radio at the top of the hour. They are officially called the Greenwich Time Signal.
How they work
The signal is six tones: five short pips and one longer. The start of the final, longer tone marks the exact hour. It was first broadcast by the BBC in 1924 and has been a fixture of British radio since.
Why digital radio can be late
Digital radio and streaming involve processing and buffering, so the pips can arrive several seconds after the real hour. FM and long-wave are closer to the true time, which is why the signal is a poor way to set a precise clock on a digital service.
Frequently asked questions
When did the pips start?
The BBC first broadcast the Greenwich Time Signal in 1924.
Clock change guides
- What Is Daylight Saving Time (DST)? A Plain-English GuideWhat daylight saving time is, how it works in the UK, Europe and the US, why it exists, its history, who uses it and the argument over scrapping it.
- Why Do the Clocks Go Back in October? The Real ReasonThe clocks go back in autumn to return the UK to GMT, so winter mornings are lighter. The history, the rule, what time it happens and what changes for you.
- When Do the Clocks Go Forward Again After Going Back?When the UK clocks go forward again after the autumn change, how long the UK stays on GMT, when evenings get lighter and how to remember to reset your clocks.