You're watching a One Day International. One team has piled up 300. Then rain arrives, the covers come on, and when play resumes, the chasing team's target isn't 300 anymore — it's some oddly specific number like 226 from 30 overs. Commentators start talking about “the DLS par score,” and half the stadium quietly has no idea what that means.
You're not alone. DLS looks like magic from the outside, but underneath it's just careful, logical math. This guide breaks it down in plain language — no jargon left unexplained — and by the end, you'll be able to work out a rough DLS target yourself with nothing but a calculator.
Here is what we will cover:
- What DLS actually is, and the simple idea it's built on
- Why cricket needed it in the first place (the infamous 1992 story)
- The real formula DLS uses — explained step by step
- Fully worked examples you can follow with pen and paper
- Why targets sometimes go up, not down, after rain
- What a “par score” is and how to read one during a match
- Common myths about DLS, busted
What Is the Duckworth-Lewis-Stern (DLS) Method?
DLS is the system cricket uses to work out a fair target when rain or any other stoppage cuts short a limited-overs match (ODIs and T20s). It is named after the two statisticians who invented it, Frank Duckworth and Tony Lewis, and Steven Stern, who updated it later for the modern game.
The core concept behind DLS is straightforward: batting an innings isn't just about time, it's about resources. Every team has two resources to spend over the course of an innings:
- Overs remaining — how much time is left to score runs
- Wickets remaining — how much risk the batting unit can afford to take
Think of it like a road trip with a fuel tank and a time limit. A team with 20 overs left and 9 wickets in hand is like a car with a full tank and plenty of time — it can accelerate aggressively. A team with 20 overs left but only 2 wickets is like a car running on fumes — it must proceed cautiously or risk getting bowled out. DLS mathematically assigns a value to how much “fuel” each team has at any moment, known as a resource percentage.
Why DLS Was Invented: The 1992 World Cup Fiasco
Before DLS, cricket used a method called Most Productive Overs (MPO). It simply deleted a bowling team's least productive overs from the equation when overs were lost — a method with no genuine cricketing logic.
It collapsed spectacularly during the 1992 World Cup semi-final between South Africa and England. South Africa needed a gettable 22 runs off 13 balls when a 12-minute rain delay hit. Under MPO, the target was recalculated to an impossible 22 runs off 1 ball — an outcome that abruptly decided a World Cup knockout match.
That single match drove Duckworth and Lewis to create a system where revised targets reflected actual batting potential rather than arbitrary mathematical reductions.
| Year | Milestone / Evolution |
|---|---|
| 1992 | The World Cup semi-final disaster exposes the flaws of older rain-rule systems. |
| 1997 | Frank Duckworth and Tony Lewis publish the original D/L model. |
| 1999 | The ICC officially adopts Duckworth-Lewis for international ODI cricket. |
| 2014 | Statistician Steven Stern recalibrates the model for modern aggressive batting and T20 cricket, forming “DLS.” |
The Actual DLS Formula Explained
DLS determines revised totals through two core formulas based on resource availability:
Formula 1: Only the chasing team's innings is interrupted
This is the standard case — Team 1 completed their full quota of 50 overs (100% resources), and Team 2's overs are shortened.
Formula 2: Both innings are interrupted (or Team 1's innings ends prematurely)
When Team 1's innings is curtailed, an ICC benchmark constant called G50 (the average score expected in a full 50-over innings, set around 245–250) is used to balance lost opportunities.
If Team 2's Resources > Team 1's Resources:
Par Score = Team 1's Score + [G50 × (Team 2's Resource % − Team 1's Resource %) ÷ 100]
If Team 2's Resources < Team 1's Resources:
Par Score = Team 1's Score × (Team 2's Resource % ÷ Team 1's Resource %)
The Resource Table
Resource percentages are referenced from statistical tables compiled from international cricket data:
| Overs Remaining | 0 Wickets Lost | 2 Wickets Lost | 5 Wickets Lost | 8 Wickets Lost |
|---|---|---|---|---|
| 50 Overs | 100.0% | 83.8% | 49.5% | 20.0% |
| 40 Overs | 89.3% | 77.6% | 47.6% | 19.7% |
| 30 Overs | 75.1% | 67.3% | 44.1% | 19.0% |
| 20 Overs | 56.6% | 52.4% | 37.6% | 17.5% |
| 10 Overs | 32.1% | 30.8% | 24.6% | 13.5% |
| 5 Overs | 17.2% | 16.8% | 14.7% | 9.4% |
Worked Example 1: Target Goes Down (Standard Shortened Chase)
- Team 1 scores 300 in a full 50 overs (used 100% resources).
- Rain cuts Team 2's chase to 30 overs before they start batting (all 10 wickets available).
- From the resource table: 30 overs remaining, 0 wickets down = 75.1%.
Target Calculation:
Target = 300 × (75.1 ÷ 100) + 1 = 225.3 + 1 → 226 runs to win in 30 overs.
Worked Example 2: Why the Target Can Actually Go UP
When the first batting team has their innings cut short unexpectedly, the chasing target often increases.
- Team 1 prepares for 50 overs. They bat steadily to preserve wickets, reaching 90/1 in 20 overs.
- Sudden rain stops play permanently for Team 1. The match is reduced to 20 overs per side, locking Team 1's total at 90.
- Team 1 used roughly 29% of baseline resources because they were denied the high-scoring late overs they were saving wickets for.
- Team 2 gets a fresh 20-over innings with all 10 wickets intact (56.6% resources from the table).
Because Team 2's resources (56.6%) exceed Team 1's used resources (29%), Formula 2 applies with a $G50$ of 245:
Par Score = 90 + [245 × (56.6 − 29) ÷ 100] = 90 + (245 × 0.276) = 90 + 67.6 = 157.6
Target: Team 2 needs 158 runs to win in 20 overs (68 runs higher than Team 1's total). This compensates Team 1 for having built an innings around a 50-over format, while Team 2 knows from ball one they only need to sprint for 20 overs.
DLS Par Score vs. Revised Target
- Revised Target: The total runs the chasing team needs to win if the scheduled overs are completed.
- Par Score: The exact minimum score the chasing side must reach by a specific ball/over mark to be level if the match is terminated immediately.
Minimum Overs Required for an Official Result
- One-Day Internationals (ODIs): Both sides must bat at least 20 overs (unless a team is bowled out earlier).
- T20 Internationals & Leagues (IPL, BBL): Both sides must bat at least 5 overs.
If these over minimums are not met, the match is declared a No Result.
Common DLS Myths, Busted
- Myth: DLS assumes runs come at a constant rate.
Fact: DLS models cricket non-linearly. Scoring naturally accelerates toward the death overs; the formula weights overs with multiple wickets in hand much higher than early consolidation overs. - Myth: DLS favors the team chasing.
Fact: DLS only balances resources used versus resources remaining. A chasing team that loses early wickets will see their required par score escalate rapidly. - Myth: Match officials calculate DLS manually.
Fact: Umpires and ICC statisticians utilize certified DLS Professional software that updates dynamically with live match data.
Frequently Asked Questions
Does DLS apply to Test cricket?
No. Test matches do not have scheduled over limits per innings and are decided across five days over session play.
Can a DLS target be revised more than once in a single match?
Yes. If recurrent rain stoppages occur, match officials input updated overs and wicket states at each stoppage to generate a newly revised target.
What is the difference between D/L Standard and DLS Professional?
D/L Standard relied on static reference tables built for 1990s scoring patterns. DLS Professional uses dynamic software to accurately handle modern high-scoring totals like 350+ in ODIs or 220+ in T20s.
Can fans calculate a DLS target manually during a match?
Roughly, yes. Using the core DLS formulas and standard resource percentage tables, fans can approximate the target very closely, though official match software interpolates ball-by-ball precision.