Batting average explained: why not-outs change the number

Batting average is the oldest and most quoted statistic in cricket. It answers a simple question: how many runs does this batter score, on average, before being dismissed? The word that matters is dismissed. The denominator is not the number of innings, it is the number of times the batter was out.

That one detail explains why a batter with several not-outs can have an average that looks higher than their typical score, and why a batter who has never been dismissed has no average at all.

The formula

Batting average = total runs ÷ (innings − not-outs)

Take six fictional innings: 42, 18 not out, 65, 7, 30 not out and 0. Total runs are 42 + 18 + 65 + 7 + 30 + 0 = 162. There are six innings and two not-outs, so four dismissals. The average is 162 ÷ 4 = 40.50.

If you divided by innings instead, you would get 162 ÷ 6 = 27.00. That figure is a runs-per-innings number, which is a different statistic. Cricket records use runs per dismissal.

How a not-out lifts the average

A not-out innings adds runs to the total without adding a dismissal. Suppose a batter has 150 runs from five dismissals, an average of 30.00. They then score 20.

• If they are dismissed on 20, the total becomes 170 across six dismissals: 170 ÷ 6 = 28.33.
• If they finish not out on 20, the total is 170 across five dismissals: 170 ÷ 5 = 34.00.

The same 20 runs move the average in opposite directions depending on whether the innings ended with a wicket. This is by design: a not-out batter has shown they could keep scoring, and the statistic does not penalise them for the innings ending without a dismissal. It does mean that finishing a limited-overs innings unbeaten flatters the average of a batter who often bats late.

A batter who retires hurt is recorded as not out. A batter who is retired out by the team is treated as dismissed, though competitions describe this in their own scoring rules.

When there is no average

If a batter has never been dismissed, the denominator is zero and the average is undefined. A batter with a single innings of 54 not out has no batting average. Scorecards and record books usually show a dash. Do not report 54.00, which would imply a dismissal that did not happen. The calculator on this site returns a clear message instead of a misleading number.

Average and strike rate answer different questions

Average measures how much a batter scores before being dismissed. Strike rate measures how quickly. Put them together and you can calculate how many balls a batter typically faces per dismissal.

Both batters scored 400 runs. B has the higher average and the much higher strike rate. A faces more balls before dismissal, which is a form of durability, and in a Test that might be the quality the side wants. In a T20 chase, B’s numbers would be far more useful.

The relationship is simple: balls per dismissal = average ÷ (strike rate ÷ 100). For A, 40 ÷ 0.80 = 50. For B, 50 ÷ 1.3333 = 37.5.

Reading an average sensibly

Averages are only as meaningful as the sample behind them.

• Sample size. An average of 60 from three dismissals says much less than 45 from forty. Look at the number of innings.
• Format. Averages in Test cricket, one-day cricket and T20 cricket are not directly comparable because the batters’ jobs differ.
• Conditions. Pitch, opposition and era all influence what a good average means.
• Distribution. An average of 40 could come from steady scores in the 30s and 40s, or from a single double century and many small scores. Medians and consistency measures are not in the basic statistic.

The guide to reading a scorecard shows where innings, not-outs and dismissals are listed so you can rebuild the figure yourself.

Common mistakes

• Dividing by innings rather than dismissals.
• Counting a retired-hurt innings as a dismissal.
• Reporting an average for a batter who has never been dismissed.
• Averaging separate averages instead of adding runs and dismissals first, a mistake the calculation mistakes guide covers with examples.

Practice questions with answers

Try these on your own first, then compare with the answers.

Question 1. Scores: 55, 12*, 0, 33, 71*, 9. What is the average?

Answer. Runs 180, two not-outs in six innings so four dismissals. 180 ÷ 4 = 45.00.

Question 2. A batter has 1,200 runs from 30 innings with 6 not-outs. What is the average?

Answer. Dismissals are 24. 1,200 ÷ 24 = 50.00.

Question 3. A batter has 600 runs, 20 dismissals and 480 balls faced. What are the average, strike rate and balls per dismissal?

Answer. Average 600 ÷ 20 = 30.00. Strike rate 600 ÷ 480 × 100 = 125.00. Balls per dismissal 480 ÷ 20 = 24.

How this guide was checked

Published by CricketCals. Every match, score and player in this guide is a fictional teaching example, so you can reproduce each answer from the figures shown. Calculations keep full precision until the final rounding. If a published scorecard or a competition rule disagrees with a figure here, the official record and the event's playing conditions take priority. You can send a correction with the figures and the rule you used.

• MCC Laws of Cricket: Laws on the batter’s innings and how dismissals are recorded.
• ICC playing conditions: Event rules for retirement and substitutions.