The CEILING function in Excel is a mathematical function that allows users to round a number up to the nearest integer or multiple of a specified number. This function is useful when you need to round up a number to a certain level, such as when you are working with financial data and need to round up to the nearest dollar or when you need to round up to the nearest multiple of a number.

The syntax for the CEILING function is CEILING(number, significance). The number argument is the number that you want to round up, and the significance argument is the multiple to which you want to round up the number.

For example, if you want to round up the number 12.34 to the nearest multiple of 0.1, you would use the CEILING function as follows: =CEILING(12.34, 0.1). This would return the value 12.4, since 12.4 is the nearest multiple of 0.1 to 12.34.

There are a few key things to keep in mind when using the CEILING function in Excel. First, the CEILING function always rounds up, so if the number you are working with is already at or above the multiple you are specifying, the CEILING function will not change it. For example, if you use the CEILING function to round up the number 12.34 to the nearest multiple of 0.1 and the result is 12.4, using the CEILING function again on the number 12.4 with a significance of 0.1 will not change the result.

Second, you can use the CEILING function to round up to a multiple of a negative number. For example, if you want to round up the number 12.34 to the nearest multiple of -0.1, you would use the CEILING function as follows: =CEILING(12.34, -0.1). This would return the value 12.3, since 12.3 is the nearest multiple of -0.1 to 12.34.

Third, if the significance argument is not a multiple of 1, the CEILING function will return a decimal value. For example, if you use the CEILING function to round up the number 12.34 to the nearest multiple of 0.1, the result will be a decimal value of 12.4. If you want to round up to the nearest integer, you can use the INT function in combination with the CEILING function. For example, to round up the number 12.34 to the nearest integer, you would use the following formula: =INT(CEILING(12.34, 1)). This would return the value 13, since 13 is the nearest integer to 12.34.

The CEILING function can be used in a variety of ways in Excel. Here are a few examples of how you might use the CEILING function in your work:

- Rounding up to the nearest dollar: If you are working with financial data and want to round up all of your values to the nearest dollar, you can use the CEILING function with a significance of 1. For example, if you have a cell with the value $12.34, you can use the following formula to round it up to the nearest dollar: =CEILING(A1, 1). This would return the value 13, since 13 is the nearest dollar to 12.34.