The date math expressions consist either adding some quantity of time in a specified unit, or rounding the current time by a specified unit. Expressions can be chained and are evaluated left to right.
For example, to represents a point in time two months from now, use:
NOW+2MONTHS
To represents a point in time one day ago, use:
NOW-1DAY
A slash is used to indicate rounding. To represents the beginning of the current hour, use:
NOW/HOUR
To represent a point in time six months and three days into the future and then rounds that time to the beginning of that day, use:
NOW+6MONTHS+3DAYS/DAY
While date math is most commonly used relative to NOW, it can be applied to any fixed moment in time as well:
1972-05-20T17:33:18.772Z+6MONTHS+3DAYS/DAY
Note: Solr 6 date math supports TODAY.