You can change the negative numbers to positive numbers with following steps:

1. Enter number -1 in a blank cell, then select this cell, and press Ctrl + C keys to copy it.

2. Select all negative numbers in the range, right click, and select Paste Special… from the context menu. See screenshot:

Notes:
(1) Holding Ctrl key, you can select all negative numbers with clicking them one by one;
(2) If you have Kutools for Excel installed, you can apply its Select Special Cells feature to select all negative numbers quickly. Have a Free Trial!

3. And a Paste special dialog box will be displayed, select All option from Paste, select Multiply option from Operation, click OK. See screenshot:

4. The all selected negative numbers will be converted into positive numbers. Delete the number -1 as you need. See screenshot:

Easily change negative numbers to positive in the specified range in Excel

Comparing to removing the negative sign from cells one by one manually, Kutools for Excel's Change Sign of Values feature provides an extremely easy way to quickly change all negative numbers to positive in selection. Full Feature Free Trial 30-day!

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As an Excel professional, also you can run the VBA code to change the negative numbers to positive numbers.

1. Press Alt + F11 keys to open the Microsoft Visual Basic for Applications window.

2. There will be a new window displayed. Click Insert > Module, then input the following codes in the module:

Sub Positive
Dim Cel As Range
For Each Cel In Selection
If IsNumeric(Cel.Value) Then
Cel.Value = Abs(Cel.Value)
End If
Next Cel
End Sub

3. Then click Run button or press F5 key to run application, and all negative numbers will be changed to positive numbers. See screenshot:

Most of Excel users don’t want to use VBA code, are there any quick tricks for changing the negative numbers into positive? Kutools for excel can help you easily and comfortably to achieve this.

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1.  Select a range including the negative numbers you want to change, and click Kutools > Content > Change Sign of Values.

2. Check Change all negative values to positive under Operation, and click Ok. See screenshot:

Now you will see all negative numbers change to positive numbers as shown as below:

Note: With this Change sign of Values feature, you also can fix trailing negative signs, change all positive numbers to negative, reverse the sign of all values and change all negative values to zero. Have a Free Trial!

(1) Quickly change all positive values to negative in the specified range:

(2) Easily reverse the sign of all values in the specified range:

(3) Easily change all negative values to zero in the specified range:

(4) Easily fix trailing negative signs in the specified range:

Kutools for Excel - Includes more than 300 handy tools for Excel. Full feature free trial 30-day, no credit card required! Get It Now

Change positive numbers to negative

Reverse signs of values in cells

Fix trailing negative signs in cells

Change negative number to zero