This guide shows you how to convert balls to overs and overs back to balls, the way a scorer does it. You’ll also learn how to add two bowling spells, count the balls left in an innings, and know when a figure like 16.4 has to become 16.67.
Quick Answer
To convert balls to overs, divide the number of legal balls by 6. The whole number is the completed overs, and the remainder is the extra balls, written after the point. So 100 balls is 16 overs and 4 balls, written 16.4 overs. To go back, multiply the overs by 6 and add the extra balls.
What Counts as a Ball in an Over
Under MCC Law 17.1, an over is six balls. Law 17.3 makes clear that only valid balls count towards those six. A wide or a no-ball doesn’t count, and neither does a ball called dead before the striker has had a chance to play it.
That’s why an over can last seven, eight or more deliveries. If a bowler sends down one wide and one no-ball in an over, eight deliveries are bowled, but the over still contains only six valid balls. The score moves on from 8.0 overs to 9.0 overs, not further.
So when this guide says “balls”, it means legal balls. That’s also what every scoreboard, scorecard and Criko calculator counts.
One rule organisers often ask about: under Law 17.5.1, if the umpire miscounts, the over as counted by the umpire stands. A five-ball or seven-ball over goes in the book as one over.
Formula
Overs = Legal Balls ÷ 6, written as completed overs . remaining balls
Where:
- Completed overs = legal balls ÷ 6, rounded down to a whole number.
- Remaining balls = what’s left over after taking out the completed overs (always 0 to 5).
The reverse:
Legal Balls = (Completed Overs × 6) + Remaining Balls
The digit after the point can only be 0, 1, 2, 3, 4 or 5. A sixth ball completes the over, so 12 overs and 6 balls is never written with a 6. It’s 13.0.
Step-by-Step Calculation
How many overs is 100 balls? It’s a common search, partly because of 100-ball cricket. In six-ball overs, the working is:
- Divide by 6: 100 ÷ 6 = 16, with a remainder.
- Completed overs: 16 × 6 = 96 balls, so 16 full overs.
- Remaining balls: 100 − 96 = 4.
- Write it in cricket notation: 16.4 overs.
Read that as “sixteen point four” on a scoreboard, but it means sixteen overs and four balls. It isn’t sixteen and four-tenths.
One more: 77 balls. 12 × 6 = 72, and 77 − 72 = 5, so 77 balls is 12.5 overs: one ball short of 13 overs.
Overs to Balls: The Reverse Conversion
Scorers need this one constantly, because you can’t subtract or add overs safely until they’re in balls.
An ODI innings that closes at 31.4 overs:
- Completed overs: 31 × 6 = 186.
- Add the extra balls: 186 + 4 = 190 legal balls.
A tennis-ball side’s innings that ends at 8.3 overs: 8 × 6 = 48, plus 3, gives 51 balls.
Adding and Subtracting Overs Without Errors
This is where paper scoresheets go wrong. Overs don’t add like ordinary decimals, because each “unit” after the point is one-sixth of an over, not one-tenth.
Adding two spells. A bowler bowls 2.4 overs early and 1.5 overs at the death. Add them as decimals and you get 4.9, which is impossible notation. Do it in balls instead:
- 2.4 overs = 16 balls.
- 1.5 overs = 11 balls.
- Total: 16 + 11 = 27 balls.
- Back to overs: 27 balls = 4.3 overs.
Balls left in an innings. In a 20-over game, 13.2 overs have been bowled. The decimal shortcut, 20 − 13.2 = 6.8, is also impossible notation. In balls:
- Innings length: 20 × 6 = 120 balls.
- Bowled: 13.2 overs = 80 balls.
- Left: 120 − 80 = 40 balls, which is 6.4 overs.
The habit to build: convert to balls, do the sum, convert back.
Decimal Overs: When You Need Them
There’s a third way to write overs, and it’s only for dividing. Rates such as run rate and economy rate divide by the true number of overs, which is balls ÷ 6.
| Balls | Cricket notation | Decimal overs (for rate maths) |
|---|---|---|
| 40 | 6.4 | 6.67 |
| 77 | 12.5 | 12.83 |
| 100 | 16.4 | 16.67 |
| 190 | 31.4 | 31.67 |
Here’s why it matters. A side scores 145 in 16.4 overs. The correct run rate divides by 16.67 decimal overs and gives 8.70 runs per over. Divide by 16.4 instead and you get 145 ÷ 16.4 = 8.84, which is wrong by about 0.14 an over. Mistakes like that flip close net run rate tables.
Use the notation (16.4) on the scoresheet and the decimal (16.67) only inside a division.
Important Points
- Only legal balls count. Wides and no-balls are extra deliveries, not extra balls in the over (Law 17.3).
- The digit after the point stops at 5. If your sum gives x.6 or more, it’s wrong. Carry into the next over.
- Never add or subtract notation directly. Convert to balls first. This applies to bowling figures, team overs and balls left.
- Decimal overs are for division only. Writing 16.67 overs on a scorecard confuses everyone. Writing 16.4 into a run-rate formula gives the wrong rate.
- Five-ball formats are different. In 100-ball cricket the “sets” are five balls, so these six-ball conversions don’t apply there.
Another Example: Bowling Quotas in a 16-Over Match
Organisers often need overs arithmetic before a ball is bowled, when they set how much each bowler may bowl.
The ICC’s T20I playing conditions show one way to do it. Clause 13.9.1 limits a bowler to 4 overs in a 20-over innings. When a match is reduced, clause 13.9.2 limits each bowler to one-fifth of the innings overs. If the overs don’t divide exactly by 5, one more over is allowed to cover the balance.
Applied to a 16-over local match (this is our worked illustration, not a rule your league must follow):
- One-fifth of 16 overs: 16 ÷ 5 = 3, with 1 over left.
- Five bowlers at 3 overs each cover 15 overs, so one more over is needed.
- So the maximum is 4 overs per bowler, which is 4 × 6 = 24 balls.
If a bowler bowls 2.4 overs and then 1.2 overs, that’s 16 + 8 = 24 balls: exactly the 4-over quota, and nothing left. Write your league’s quota rule into your playing conditions before the tournament, so the scorer and both captains are counting the same way.
Frequently Asked Questions
How many overs is 100 balls?
In six-ball overs, 100 balls is 16 overs and 4 balls, written 16.4 overs. That’s because 16 overs use 96 balls, leaving 4. For run-rate maths, the same figure is 16.67 decimal overs.
Does 12.5 overs mean twelve and a half overs?
No. In cricket notation, 12.5 means 12 overs and 5 balls, which is 77 balls. Twelve and a half overs would be 12.3 in cricket notation (75 balls).
How do you add overs in cricket?
Convert each figure to balls, add the balls, then convert back. For example, 2.4 overs (16 balls) plus 1.5 overs (11 balls) is 27 balls, which is 4.3 overs, not 4.9.
Do wides and no-balls count as balls in an over?
No. Under MCC Law 17.3, wides and no-balls are not valid balls, so they don’t count towards the six. The bowler has to bowl another delivery for each one, which is why some overs last more than six deliveries.
What are decimal overs used for?
Decimal overs (balls ÷ 6) are used only when you divide by overs, for example for run rate, economy rate and net run rate. Scorecards always show cricket notation, such as 16.4, not 16.67.
What happens if the umpire bowls a five-ball or seven-ball over by mistake?
Under MCC Law 17.5.1, the over as counted by the umpire stands. It goes in the book as one over, and the next over starts as normal.
Related Criko Tools
- Balls to overs converter: turns any number of legal balls into overs notation and decimal overs.
- Overs to balls converter: turns notation like 31.4 into 190 balls.
- Run rate calculator: handles the decimal-overs step for you.
Related Cricket Guides
Conclusion
To convert balls to overs, divide by 6 and write the remainder after the point. To go back, multiply by 6 and add the balls. Do every addition and subtraction in balls, and switch to decimal overs only when you’re dividing to find a rate.