The DLS Method Explained: How Cricket Sets a Target After Rain
When rain or bad light shortens a one-day or T20 match, the team batting second cannot simply chase the same total in fewer overs. The Duckworth-Lewis-Stern (DLS) method sets a fair new target. This guide explains the idea behind it without the maths.
Why cricket needed a better rain rule
Older rain rules only looked at overs. The most famous failure came in the 1992 World Cup semi-final between England and South Africa. After a short rain break, South Africa's target went from 22 needed off 13 balls to 21 needed off one ball, because the rule removed the overs without reducing the target fairly.
Statisticians Frank Duckworth and Tony Lewis designed a new method that was first used in international cricket in 1997 and adopted by the ICC in 1999. Professor Steven Stern later updated it for modern scoring rates, and it was renamed Duckworth-Lewis-Stern in 2014.
The key idea: resources
A batting team has two resources: the overs it has left and the wickets it has left. Losing overs costs a team less if it has already lost many wickets, because it could not have used those overs fully anyway. Losing overs early, with all ten wickets in hand, costs a lot.
DLS works out what share of its total resources each team actually had. If the side batting second had fewer resources than the side batting first, its target is reduced in proportion. If it had more, for example because the first innings was cut short, its target goes up.
Par score
When play stops for good during the second innings, the result depends on the par score: the score the chasing side should have reached for the overs and wickets used. If the chasing team is ahead of par, it wins. If it is behind, it loses. If it is exactly on par, the match is a tie.
Minimum overs for a result
- ODIs: each side must face at least 20 overs for a result, unless the team batting second has already passed its target.
- T20 Internationals: each side must face at least five overs.
If rain prevents that, the match is a no result. That is exactly what happened in a recent India vs West Indies T20I, explained in our article on the five-over rule.
Why some fans still find it confusing
The official calculation uses a computer program, so fans cannot work out the exact target in their heads. Broadcasters show the par score after each over during rain-affected chases, which is the easiest way to follow who is ahead.
For more on how limited-overs cricket is scored and ranked, see our run rate calculator and the cricket rules guide.