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Seconds

To get the number of seconds in a duration, use dayjs.duration().seconds().

It will return a number between 0 and 59.

dayjs.duration(500).seconds(); // 0
dayjs.duration(1500).seconds(); // 1
dayjs.duration(15000).seconds(); // 15

If you want the length of the duration in seconds, use dayjs.duration().asSeconds() instead.

dayjs.duration(500).asSeconds(); // 0.5
dayjs.duration(1500).asSeconds(); // 1.5
dayjs.duration(15000).asSeconds(); // 15