- Select the cell(s) with the formula(s) you want to hide.
- From the Format Cells dialog box, go to the Protection tab.
- Click OK.
(If you want to allow entering or editing data on certain cells, select those cells and follow step 2 and 3. Then uncheck the Locked check box and click OK.)
Now you can protect your worksheet.
- From Home tab, click Format from Cells group and select Protect Sheet... or you can also find Protect Sheet button in the Changes group from Review tab (for earlier versions, go to Tools menu, point at Protection and select Protect Sheet...).
- Apply your password to protect (optional) and repeat the same password after clicking OK.
REMINDER! Password is case sensitive. To unprotect, you must type the password exactly like the one you've created. If you forgot the password then you can say good bye to your worksheet :).