Duckworth–Lewis–Stern (DLS) Explainer
Duckworth–Lewis–Stern (DLS) Explainer
What the DLS method does, why a simple run-rate target is unfair to the side chasing, and where your official revised target actually comes from. This page deliberately computes no target: the current Professional Edition’s resource values are not published and its software is not sold.
Where your revised target comes from
Explainer, not a calculatorProfessional Edition, chase shortened, 12 overs lost
Why a run-rate target is unfair to the side chasing
| Side batting first | Side chasing, run-rate target | Side chasing, resource-based target | |
|---|---|---|---|
| Overs available | 50 | 25 | 25 |
| Wickets available | 10 | 10 | 10 |
| What it can plan | pace an innings over 50 overs, holding wickets back | must score at the same rate over half the overs | target set by what 25 overs with 10 wickets is worth |
| The asymmetry | overs are the binding constraint | wickets are no longer binding, so the rate is easier to sustain | the extra freedom is priced in |
| Effect of a run-rate target | — | systematically too easy for the chasing side | — |
The two editions, and what is public about each
| Standard Edition | Professional Edition | |
|---|---|---|
| Status | superseded; still specified by some competitions | current, and used in international cricket |
| How it works | a fixed table of resource percentages by overs and wickets | a program whose percentages also vary with the score |
| Can it be worked by hand? | yes, which is why it survives | no — the ICC’s D/L FAQ Q7 says it “requires use of a computer program” |
| Are the numbers published? | a table is linked from the ICC’s own DLS page, and FAQ Q27 says the full tables are available to cricket authorities | no. The resource values are not publicly available |
| Is the software available? | not applicable | FAQ Q28: “not yet available for sale to the general public” |
| Could this site reproduce it? | no. Could not establish that it is free to republish, which is a weaker and different finding from saying it is encumbered | no, and there is nothing to reproduce |
What this page can and cannot do
| Here | Elsewhere | |
|---|---|---|
| Explain what the method is for | yes | — |
| Say which edition your competition uses | no — ask the organiser | your competition’s playing conditions |
| Give a revised target | no | the match officials’ DLS software |
| Give a par score | no | the match officials’ DLS software |
| Work the chase from a target you already have | no | the required run rate page |
| Feed a DLS result into a group table | no | the net run rate page, under ICC clause 16.10.2 |
What DLS does, and why this page will not give you a target
When rain takes overs out of a limited-overs match, somebody has to decide what the side batting second now needs. Doing it on run rate alone is unfair, and the unfairness has a direction. A side given 25 overs instead of 50 still has all ten wickets, so wickets stop being the binding constraint and it can attack from the first ball; setting it the first innings’ run rate over half the overs therefore makes the chase easier than the innings it is being compared with. The Duckworth–Lewis–Stern method exists to price that in. It treats a batting side as holding a stock of resources — overs remaining and wickets remaining, together, not either alone — expresses what is left as a percentage of a full innings, and revises the target in proportion to the resources each side actually had.
The ICC adopted the method, and its own page describes it as “a formula to fairly calculate the winning side when inclement weather intervenes and the match is interrupted”, including recalculating totals when time is lost. Which edition applies is a competition’s decision: the ICC’s D/L FAQ, updated December 2016, says at Q14 that the choice “is for the cricket authority which runs the particular competition”. There are two editions and they are not interchangeable.
The Standard Edition is the older one. Its resource percentages sit in a fixed table indexed by overs left and wickets down, so a scorer can work a revised target by hand, which is why some club and age-group competitions still specify it: no computer is guaranteed at that level. The Professional Edition is the current one and the one international cricket uses. Its percentages vary with the score as well as with overs and wickets — a side chasing 400 is in a different position from a side chasing 200 with the same overs and wickets left — and that extra dimension is why it cannot be tabulated. The ICC’s FAQ says at Q7 that the method “requires use of a computer program”.
So this page does not give you a target, and the reason is not caution for its own sake. For the Professional Edition there is nothing to reproduce: the resource values are not published, and the ICC’s FAQ says at Q28 that the software is “not yet available for sale to the general public”. A reconstructed or fitted approximation would be a different method wearing the same name, and it would be wrong in exactly the place it matters — a target is acted on within the minute it appears, by people who have no way to check it. For the superseded Standard Edition the position is different and weaker: the ICC links a Standard Edition table from its own site and its FAQ says at Q27 that the full tables are available to cricket authorities, but no licence, permission statement or fee schedule was found for republishing it. The honest record of that is could not establish that it is free to reproduce, which is not the same claim as saying it is encumbered. And there is a second reason that stands even if the first dissolves: the Standard Edition is superseded, so a target worked from it would be the wrong number for any match played under the Professional Edition, which is every international.
What a reader can usefully take from this page instead. First, that the figure on the scoreboard is the figure — revised targets and par scores come from the match officials’ software and from nowhere else, and a number from a public calculator that disagrees with the scoreboard is wrong, not interesting. Second, that “par” is a score for one exact ball, not a rate: in an abandoned chase the side batting second has won if it is ahead of par at the moment play stopped and lost if it is behind, which is why a match can be lost on the ball before a boundary. Third, that a DLS result still has to go into the group table, and the ICC has a rule for that: clause 16.10.2 of the Men’s ODI Playing Conditions credits the side batting first with the chasing side’s par score over the overs that side faced, which the net run rate calculator sets out.
Once you have the official revised target and the reduced innings length, the ordinary arithmetic is available again and the required run rate and target calculator will do it: runs still needed, balls remaining, and the rate those imply. That page does not revise targets either, for the same reason this one does not.
Frequently asked questions
Can I calculate a DLS target myself?
Not for a match played under the Professional Edition, which is every international and most professional cricket. The resource values are not published and the ICC’s own D/L FAQ says at Q28 that the software is “not yet available for sale to the general public”. Under the Standard Edition a scorer can work a target by hand from the table their competition issues.
Why does this page not have a DLS calculator?
Because it would have to be an approximation, and an approximate DLS target is a wrong target presented as an official one, in the one situation where a reader acts on it immediately. The Professional Edition’s numbers are not public, and for the superseded Standard Edition table it could not be established that republishing it is permitted — and it would be the wrong table for an international anyway.
Why is a simple run-rate target unfair?
Because overs and wickets are not interchangeable. A side given half the overs but all ten wickets can attack from the first ball, since it can no longer run out of batters before it runs out of overs. Asking it for the first innings’ run rate over half the overs is therefore easier than the innings it is being compared with. DLS counts overs and wickets together as resources.
What is the difference between the Standard and Professional Editions?
The Standard Edition reads resource percentages off a fixed table indexed by overs and wickets, so it can be worked by hand. The Professional Edition’s percentages also depend on the score, which is why the ICC’s FAQ says at Q7 that it “requires use of a computer program”. The Professional Edition is current; the Standard Edition is superseded but still specified by some competitions.
What is a par score?
The score the chasing side needs to be level at one exact point in its innings — a particular ball, with a particular number of wickets down. In an abandoned chase the side batting second has won if it is ahead of par at the moment play stopped and lost if it is behind. It is a score, not a rate, which is why a match can turn on a single ball.
How does a DLS result affect net run rate?
ICC Men’s ODI Playing Conditions clause 16.10.2 handles it: where a match is abandoned but a result is reached under DLS, the side batting first is credited with the chasing side’s par score at abandonment, over the number of overs that side faced. A match with no result at all does not enter net run rate.
Related calculators
References
- International Cricket Council. The D/L methodology: answers to frequently asked questions (updated December 2016) — Q7 (the DLS method requires use of a computer program), Q14 (the choice of edition belongs to the cricket authority running the competition), Q19 (the method is “neither a document … nor a material invention” and the authors take no royalties), Q27 (the Standard Edition tables are on the ICC website and the full tables are available to cricket authorities), Q28 (the software is not available for sale to the general public). images.icc-cricket.com (read 12 Oct 2026). The resource tables themselves are not in this document, which the document says.
- International Cricket Council. Duckworth Lewis Stern — rules and regulations page, linking the DLS Methodology, the Standard Edition table and the DLS FAQ. icc-cricket.com (read 12 Oct 2026).
- International Cricket Council. Men’s ODI Playing Conditions, clause 16: The Result — 16.3.1 (a tie is equal scores with all innings complete, regardless of wickets lost), 16.10.1 (the tiebreaker order: wins, then head-to-head, then bonus points, then net run rate), 16.10.2 (net run rate, and the full quota of overs for a side all out), 16.10.3 (run rate is runs divided by overs faced). icc-cricket.com (read 12 Oct 2026).
- Wikipedia. Duckworth–Lewis–Stern method — cited here only as corroboration for one claim the ICC’s own documents make obliquely: “The actual resource values used in the Professional Edition are not publicly available”, and the model’s constants were withheld for commercial confidentiality. A collaborative encyclopaedia is the weakest source in this list and is used for nothing else (read 12 Oct 2026).