# How DRS Works in Cricket: Reviews and Umpire's Call Source: https://cricketin.org/guides/how-drs-works [By Anjali Deshmukh](/authors/cricket-analyst), Cricket Analyst. [Reviewed by Rajeev Sathe](/authors/editor-in-chief), Editor-in-Chief. Updated 30 Aug 2026. Editorial policy: https://cricketin.org/editorial-policy 18+ Betting money on cricket carries a direct risk of financial loss, and it can become an addiction. Real-money online gaming is banned across India under the PROG Act 2025, which came into force on 1 May 2026. If betting is already costing you money you need, or sleep, or people close to you, the free Tele-MANAS helpline is **14416**, and it runs in 20 languages. Our [page on help for gambling harm](/guides/help-for-gambling-harm-india) lists what else exists. --- What can be reviewed, the 15-second rule, ball tracking and edge detection, the pitching and impact zones, umpire's call, and reviews allowed per format. The Decision Review System lets the third umpire help the on-field umpires. Players may review only two things: whether a batter is out, and most no-ball calls. A request must come within 15 seconds of the ball going dead. Test sides get three failed reviews an innings. ODI and T20I sides get two. Below we explain the pitching and impact zones. We also show why umpire's call exists, and which reviews cost you nothing. ## What DRS actually is DRS stands for Decision Review System. It is a way for the third umpire to help the two umpires on the field. The [ICC describes it](https://www.icc-cricket.com/about/cricket/rules-and-regulations/decision-review-system) as a tech-based way to help match officials make their calls. It is not a court of appeal for all that happens. There are two doors into the system. An Umpire Review is started by an on-field umpire. A Player Review is started by a team. Our clause notes below come from Appendix D of the [ICC Men's Test Match Playing Conditions](https://images.icc-cricket.com/image/upload/prd/lm8owaz03i86m1eneb7m.pdf), in force from June 2025. The same appendix sits in the [ODI conditions](https://images.icc-cricket.com/image/upload/prd/d25dbgishkx0kijb4jeu.pdf) and the [T20I conditions](https://documents.bcci.tv/bcci/documents/Mens_Twenty20_International_Playing_Conditions-Effective_December_2023.pdf). Only the review counts differ. ## What a team may and may not review The list is short, and it shocks people. A player may review just two things. - Whether a batter is dismissed, except for the timed out method. - No-ball decisions, other than a call about an illegal bowling action. Nothing else can be sent up. A team cannot review a wide or a boundary call. Nor can it review any other piece of umpire judgement. Who may ask depends on the first call. If a batter is given out, only that batter may review. If the appeal was turned down, only the fielding captain may review. The request is made with a T shape, both forearms at head height. Once made it cannot be withdrawn. ## The 15-second window A review must be asked for within 15 seconds of the ball becoming dead. The umpire prompts the players at about 10 seconds. Broadcasters hold back big-screen replays for those 15 seconds. That stops a team waiting for a replay before it asks. Players may talk, but only to each other. The two batters may confer. The captain may ask the bowler and the fielders. No help may come from the dressing room. Every DRS series also has an ICC Technical Officer. The post is an independent one. That person checks the kit, not the umpiring. ## What the third umpire looks at, in order For an lbw review, the checks run in a set order. Skip a step and the answer can change. First, was the delivery fair, or was it a no-ball? Second, did the ball hit the bat before the pad? Only then does ball tracking come in. Ball tracking then reports three things. Where the ball pitched, where it struck the batter, and whether it would have hit the stumps. Those line up with [Law 36 of the MCC Laws](https://www.lords.org/mcc/the-laws/leg-before-wicket), which sets out the five tests for lbw. Note what Law 36 adds. Only the first touch counts. If the ball hits bat and body at once, the bat counts first. **Table 1. Decision type, technology and who decides** | Decision | Main technology | Who makes the final call | |---|---|---| | LBW | Replays, edge detection, then ball tracking | On-field umpire, advised by the third umpire | | Caught behind | Slow-motion replays and sound-based edge detection | On-field umpire, advised by the third umpire | | Run out or stumping | Camera replays and lit stumps | Third umpire | | No-ball for overstepping | Camera replays of the front foot | Third umpire | | Illegal bowling action | Not reviewable at all | Handled outside DRS | In a match without DRS, the third umpire may use camera replays only. No ball tracking and no edge detection are allowed. That is why review counts do not exist in those games. ## The technology, and what it is called The ICC conditions name types of kit, not brands. They speak of ball-tracking technology and of approved sound-based edge-detection technology. The well-known names sit under those two types. [Wikipedia's DRS article](https://en.wikipedia.org/wiki/Decision_Review_System) lists Hawk-Eye or Virtual Eye for ball tracking. For sound it lists Real Time Snicko and Ultra-Edge. It also lists Hot Spot infra-red imaging, and dates the system to 2008. Brand names change with the host board and the TV firm. We still need to know which sound-based edge-detection brand is approved for a given series. That has to come from an ICC or host-board document, not a news report. The playing conditions name no brand at all. For a viewer, the point is simpler. The third umpire reads a sound spike against the exact frame the ball passes the bat. A spike one frame late is not an edge. ## The pitching zone and the impact zone Two unseen zones do most of the work in an lbw review. The conditions define them with care. The Pitching Zone is a flat area between the two sets of stumps. Lines just outside the outer stumps mark its edges. Where the ball pitched is judged by the centre of the ball. It is given as In Line, Outside Off or Outside Leg. Outside Leg means not out. The Impact Zone is a 3D space between the wickets, with no height limit. The same lines outside the outer stumps mark its edges. Impact is In Line when the centre of the ball is inside the zone. It is Umpire's Call when part of the ball is inside but the centre is out. It is Outside when no part of the ball is inside. Wicket is judged against the outline of the stumps and bails. The ICC set out that wicket zone in its [note on playing condition changes](https://www.icc-cricket.com/news/several-changes-made-to-icc-playing-conditions). ## Umpire's call, and why it makes people angry Umpire's call means the kit is not sure enough to overrule the human. The first call stands. It can crop up twice in one lbw review. Once on impact, and once on whether the ball would have hit the stumps. Here is the part that upsets fans. The same ball can be out for one team and not out for the other. It all hangs on what the umpire said first. The kit is the same. Only the start point differs. The conditions build in a gap that explains it. Take a case where a real shot was offered. To turn a not out into an out, impact must be In Line. To turn an out into a not out, impact must be Outside. Anything in between leaves the umpire's call alone. Fans of the rule make a fair point. Ball tracking maps a path the ball never took. So a margin of error is honest. Critics reply that a fixed margin helps whoever guessed first. The trade-off is a good one for teams. An lbw review lost to umpire's call does not count against the side's quota. ## How many reviews each side gets The number depends on the format. The count is per team per innings. Only failed reviews count. **Table 2. Unsuccessful Player Reviews allowed per team per innings** | Format | Allowance | Source | |---|---|---| | Test | 3 | [ICC Test PCs, Appendix D](https://images.icc-cricket.com/image/upload/prd/lm8owaz03i86m1eneb7m.pdf) | | ODI | 2 | [ICC ODI PCs, Appendix D](https://images.icc-cricket.com/image/upload/prd/d25dbgishkx0kijb4jeu.pdf) | | T20I | 2 | [ICC T20I PCs, Appendix D](https://documents.bcci.tv/bcci/documents/Mens_Twenty20_International_Playing_Conditions-Effective_December_2023.pdf) | The T20I figure needs a caveat. The full document we could open is the December 2023 edition. The ICC's [playing conditions page](https://www.icc-cricket.com/about/cricket/rules-and-regulations/playing-conditions) lists July 2025 as current. We still need to check the T20I review count against that July 2025 edition. One myth is worth killing. The Test conditions we read do not top up reviews after 80 overs. We looked for that line and did not find it. ## Which reviews count against you This is where the book-keeping matters. Some results leave your quota untouched. - The call is reversed: not counted. - The call stands as umpire's call: not counted. - The batter stays not out because the ball was a no-ball: not counted. - An umpire review made your own request needless: not counted. - The call stands on the merits: counted as a failed review. - The kit fails during the review: the match referee may give the review back. So a captain has more room than the headline number suggests. A team can review five times and still hold three, if the calls go its way. ## Why the formats treat reviews differently A Test innings can last 150 overs. A T20 innings lasts 20. Per over, three reviews in a Test is far tighter than two in a T20. Time matters too. A three-hour T20 cannot soak up long delays. So short formats keep the count low. For the wider rules of each format, see our [Test cricket guide](/guides/test-cricket-explained), our [50-over guide](/guides/odi-rules-explained) and our [T20 guide](/guides/t20-rules-explained). The [formats overview](/guides/cricket-formats-explained) compares them in one table. ## How we checked this page DRS rules have changed more than once. The umpire's call margins changed, and so did the wicket zone. So we read the current documents rather than trust memory. Every fact above comes from ICC playing conditions, an ICC news note, the MCC Laws or the ICC's own DRS page. We read them in August 2026. Where a document names no brand, we did not invent one. Our [verification method](/how-we-test) explains the standard. Fixes are logged on our [corrections page](/corrections). Every explainer is listed on the [guides hub](/guides). ## Questions people ask ### Can a team review a wide? No. Player reviews cover only two things. One is whether a batter is out. The other is no-ball calls, apart from a call about an illegal bowling action. A wide is not on the list. ### Why does umpire's call keep the original decision? Ball tracking maps a path the ball never took. So a margin of doubt is built in. Say part of the ball is inside the zone but its centre is outside. The kit is then not treated as proof. ### Does a review lost to umpire's call use up a review? No. Appendix D of the [ICC Test playing conditions](https://images.icc-cricket.com/image/upload/prd/lm8owaz03i86m1eneb7m.pdf) lists an unchanged umpire's call as not counted. Only calls that stand on the merits use up a review. ### How long does a team have to ask for a review? Fifteen seconds from the ball becoming dead. The umpire prompts at about ten seconds. Big-screen replays are held back for the full fifteen. So teams cannot wait to see one. ### What happens in a match played without DRS? The third umpire may use camera replays only. No ball tracking and no edge detection are allowed. So lbw calls stay with the on-field umpire alone. ### Where does the ball have to pitch for an lbw to be given? In line with the stumps or on the off side, judged by the centre of the ball. A ball pitching outside leg stump cannot be out lbw, as [Law 36](https://www.lords.org/mcc/the-laws/leg-before-wicket) makes clear. ## More from the guides - [How Net Run Rate Works](/guides/how-net-run-rate-works) - [How Pitch Conditions Change a Cricket Match](/guides/how-pitch-conditions-work) - [How to Spot a Fake Cricket App](/guides/how-to-spot-a-fake-cricket-app) - [KYC for Online Gaming in India](/guides/kyc-in-online-gaming-india) - [ODI Cricket Rules Explained](/guides/odi-rules-explained) - [Frozen Payments in Online Gaming](/guides/payment-freeze-and-chargebacks) - [Self-Exclusion and Deposit Limits in India 2026](/guides/self-exclusion-and-limits) - [Signs of Gambling Addiction](/guides/signs-of-gambling-addiction) - [T20 Cricket Rules Explained](/guides/t20-rules-explained) - [Online Gaming Ad Rules in India](/legal/advertising-rules-online-gaming) - [GST on Online Gaming in India](/legal/gst-on-online-gaming) - [Caribbean Premier League 2026 — live schedule and table](/leagues/cpl)