Duckworth Lewis Stern (DLS) Calculator

What is the Duckworth-Lewis-Stern (DLS) Method?

The Duckworth-Lewis-Stern (DLS) method is a mathematical formulation used in limited-overs cricket to calculate revised targets when a match is interrupted, typically by rain. It was devised by statisticians Frank Duckworth and Tony Lewis and later updated by Professor Steven Stern.

The method considers that each team has two resources available: overs remaining and wickets in hand. As overs are bowled or wickets fall, the resources decrease. When a match is interrupted, the DLS method recalculates the target based on the resources available to each team.

How Does the DLS Method Work?

The DLS method assigns a percentage of resources to each combination of overs remaining and wickets lost. A team starting a 50-over innings with all 10 wickets has 100% of resources. As overs are used and wickets fall, the resource percentage decreases.

When rain interrupts a match, the resources lost due to the interruption are calculated. The revised target is then adjusted proportionally based on the resources available to the chasing team compared to the team that batted first.

• If Team 2 has fewer resources: The target is scaled down proportionally.
• If Team 2 has more resources: Extra runs are added based on the G50 value (average first innings score in 50-over cricket, currently set at 245 by the ICC).

When is the DLS Method Used?

• Rain delays during a match
• Bad light causing a stoppage
• Any interruption that reduces the number of overs in a limited-overs match
• Multiple interruptions during a single innings

DLS Method Formula

The basic formulae used in the DLS Standard Edition are:

• R1 = Resources available to Team 1
• R2 = Resources available to Team 2
• If R2 < R1: Target = S1 × R2/R1 + 1
• If R2 > R1: Target = S1 + G50 × (R2 − R1)/100 + 1

Where S1 is Team 1's score and G50 is the average first-innings score (245 for ODIs).

History of the DLS Method

Before the DLS method, cricket used the "most productive overs" method, which was widely criticized after the 1992 Cricket World Cup semi-final between England and South Africa. In that match, South Africa needed 22 runs off 13 balls when rain stopped play. After the delay, they needed 22 off just 1 ball — an absurd recalculation that highlighted the flaws of the existing system.

Frank Duckworth and Tony Lewis introduced their method in 1997, and it was first used in international cricket in 1999. Professor Steven Stern took over the management of the formula in 2014, leading to the current "DLS" name. The Professional Edition, which uses more sophisticated modelling, is used in all international and major domestic cricket, while the Standard Edition is used at lower levels.