Table of Contents for How to use dates/times in Solidity

now

The now constant will return the unix timestamp of the current block

function getTimestamp() public returns (uint) {
  return now; // num of secs since 1970-01-01
}

Units (minutes, hours, days, weeks, years)

You can use the units of minutes, hours, days, weeks, years in Solidity.

uint anHour = 60 minutes; // 60 * 60
uint halfADay = 12 * hours; // 12 * 60 * 60

Comparing dates/times in Solidity

As the units mentioned above are just units, you can use > and < like any other number.

Difference between two dates/times in Solidity

As the units mentioned above are just uints, you can use - and + to run normal math operations on them, including finding the difference with -.

Notes:

• these do not take into account num of days in a month or leap years/leap seconds

Also see how to use Ether values in Solidity

See using ether values in Solidity to use things like 1 ether or 50 wei.

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