Cricket Required Run Rate & Run Chase Calculator

Every figure here comes from three inputs — runs scored, overs bowled and (in a chase) the target. The one rule that trips people up is that overs are counted in base six: under Law 17 of the Laws of Cricket an over is six balls, so the scoreboard's 41.3 means 41 overs and 3 balls, not the decimal 41.3. The calculator converts every over figure to a whole number of balls first, which is why its rates match the TV graphic to two decimal places.

1. Overs to balls. balls = whole × 6 + ball, where the ball digit is 0–5. So 41.3 → 41 × 6 + 3 = 249 balls; 41.0 → 246 balls.
2. Innings length. An ODI innings is 50 overs = 300 balls and a T20 is 20 overs = 120 balls (ICC playing conditions). Custom lets you set 1–100 overs.
3. Balls remaining. total balls − balls bowled, shown back in over.ball form.
4. Current run rate (CRR). runs × 6 ÷ balls bowled runs per over. Runs-per-ball is simply runs ÷ balls bowled.
5. Required run rate (RRR / asking rate). In a chase, runs still needed is target − score, and RRR = runs needed × 6 ÷ balls remaining runs per over.
6. Projected score. In current-innings mode the tool extends the present pace over the full innings: round(runs ÷ balls bowled × total balls). It also shows what the final score becomes if the batting side lifts to 6, 8 or 10 runs an over for the rest of the innings.
7. Ahead or behind. The chase is on track when the current run rate is at or above the asking rate, and behind when it is below.

The projection is cross-checked two ways — current run rate × total overs, and runs-per-ball × total balls — which are algebraically identical and must return the same score, so a rounding slip would show up immediately. The maths runs entirely in your browser; nothing is sent to a server, and there is no Duckworth-Lewis rain adjustment (use the DLS calculator for that).

• MCC — Laws of Cricket, Law 17: The Over (six balls per over)
• ICC — Men's ODI & T20I Playing Conditions (innings length: 50 / 20 overs)
• MCC — the Laws of Cricket (full text)

The six-balls-per-over rule and the per-format ball counts were last cross-checked against these sources on 2026-07-08. Run rate, required run rate and projected score are standard scoring arithmetic built on that basis.