How to Round a Number in Power Apps with Round, RoundDown and RoundUp
Power Apps has three functions that round a number to the decimal places you choose. Round goes to the nearest value, RoundDown always goes down and RoundUp always goes up. 445 minutes is 7.4166… hours: Round(445 / 60, 2) makes it 7.42.
The example is the Overtime Timesheet app, which saves each shift's hours to a SharePoint column with two decimal places, and shows whole hours and minutes on screen.
Syntax
Round(Number, DecimalPlaces)
RoundDown(Number, DecimalPlaces)
RoundUp(Number, DecimalPlaces)
From Microsoft's Int, Round, RoundDown, RoundUp, and Trunc functions page:
- Round rounds up if the next digit is 5 or higher, and otherwise down.
- RoundDown always rounds down to the previous lower number, towards zero.
- RoundUp always rounds up to the next higher number, away from zero.
- DecimalPlaces is required:
2for two decimal places,0for a whole number, and a negative number to round to tens, hundreds and so on.
Step 1: Round to Two Decimal Places
I put each formula into a text control's Text for a moment, so Studio's preview strip shows the result:
Round(445 / 60, 2)
445 minutes is 7.42 hours:
Step 2: Round Down to Whole Hours
RoundDown(450 / 60, 0)
450 minutes is 7.5 hours; RoundDown keeps the 7 whole hours:
Step 3: Round Up
RoundUp(450 / 60, 0)
The same 7.5 rounded up is 8:
Which One to Use
| You want | Use | Example |
|---|---|---|
| A number to store or total, such as hours to 2 decimal places | Round | Round(445 / 60, 2) is 7.42 |
| The whole units, with the rest shown separately | RoundDown | RoundDown(450 / 60, 0) is 7, and the 30 minutes come from Mod |
| Never less than the real amount, such as blocks of time that are charged whole | RoundUp | RoundUp(450 / 60, 0) is 8 |
How the Example Uses Them
When it saves an entry, the app rounds the hours to the 2 decimal places of the SharePoint Hours column:
Hours: Round((DateDiff(Starts, Ends, TimeUnit.Minutes) - numBreakLO.Value) / 60, 2),
On screen, it shows whole hours with RoundDown and the minutes left over with Mod: How to Convert Minutes to Hours and Minutes in Power Apps.
Common Mistakes
| Mistake | What happens | Do this instead |
|---|---|---|
| Round for the whole hours of 7 h 30 min | 7.5 rounds to 8 hours | RoundDown for the whole hours |
| Leaving out DecimalPlaces | Microsoft lists it as required | Round(x, 0) for a whole number |
| Expecting rounding to add zeros | 210 / 60 shows as 3.5, not 3.50 | Text(x, "0.00") for two places |
Troubleshooting
| Symptom | Likely cause | Fix |
|---|---|---|
| Hours show 8 for 7 h 30 min | Round or RoundUp on a whole-hours part | RoundDown |
| A negative number rounds the "wrong" way | RoundDown goes towards zero, RoundUp away from it | See the table of examples on Microsoft's page |
FAQ
What about Int and Trunc?
Both make a whole number. Trunc removes the decimal part, like RoundDown(x, 0); Int goes to the lower whole number, so it differs for negative numbers: Int(-4.3) is -5 and Trunc(-4.3) is -4, from Microsoft's page.
How do I show 7.5 as 7.50?
Rounding doesn't add zeros; formatting does. Text(450 / 60, "0.00") shows 7.50, as the minutes to hours and minutes guide shows live.
Conclusion
Round to store a number to a set number of places, RoundDown for whole units with the rest shown separately, and RoundUp when the result must never be less than the real amount. All three take the number of decimal places as their second argument.
Additional Resources
- Int, Round, RoundDown, RoundUp, and Trunc functions: rules and tables of examples.
