This method will introduce the Find and Replace feature to easily replace all characters after or before specified one in Excel. Please do as follows:

1. Select the list you will replace all after/before the specific characters, and press the Ctrl + H keys simultaneously to open the Find and Replace dialog box.

Note: You can also open the Find and Replace dialog box by clicking Home > Find & Select > Replace.

2. In the Find and Replace dialog box, please do as follows：
(1) In the Find what box, please type b*;

(2) In the Replace with box, please type the text string you will replace with.
(3) Click the Replace All button.

3. Now a dialog box will come out and show how many replacements it has made. Just click the OK button to close it. And then close the Find and Replace dialog box.

And now in our example you will see all characters after b has been replaced with the specified text in the selected cells. See screenshot:

Note: This method does not work if you want to replace all characters after/before wildcards (* and ?).

Remove characters from beginning/right/end in cells

Kutools for Excel's Remove By Position feature eases you removing certain number of characters from beginning/end/specified position of text string in cells.

No mater replacing all characters after/before a normal character (such as letter, number, etc.), or replacing all after/before special character (such as *, ?, etc.), Kutools for Excel can help you easily get it done in Excel.

1. Select the list of text strings you will replace all before/after the specific character, and click Kutools > Text > Split Cells.

2. In the opening Split Cells dialog box, please check the Split to Columns option, check the Other option and type the specific character (we type the asterisk * in our example) into below box, and click the Ok button. See screenshot:

In the second Split Cells dialog box please specify the first cell of destination range and click the OK button.

And then you will see the list of text strings are split into two columns. See screenshot:

3. Select the first column of two split columns, and click Kutools > Text > Add Text.

4. In the opening Add Text dialog box, type the text you will replace with into the Text box, check the After last character option, and click the Ok button. See screenshot:

And then you will see the specified text replace all characters after the specific character (asterisk in our case). See screenshot:

Note: To replace all before the specified character, please select the second column of both split column in Step 3, and check the Before first character option in Step 4. See screenshot:

How to replace blank space with nothing/underscore/dash/comma in Excel?