How to remove space in between numbers in excel

 Method 1: Using Find & Replace - Spacebar & Empty 

This method is the quickest as it doesn't require a helper column. 

1. Select the cell, range, or entire column where you want to remove the spaces.
2. Press Ctrl + H (or Cmd + H on a Mac) to open the "Find and Replace" dialog box.
3. In the "Find what" field, press the spacebar once to insert a single space character.
4. Ensure the 
   "Replace with"
    field is 
   completely empty
   .
Click the "Replace All" button. A confirmation message will appear showing how many replacements were made. 


Method 2: Using the SUBSTITUTE Function
The SUBSTITUTE function creates a new cell with the data cleaned, leaving your original data untouched until you copy the new values over. 
1. Click an empty cell in a new column (a "helper column") next to your data.
2. In that cell, enter the formula =SUBSTITUTE(A1," ",""), replacing A1 with the address of the first cell containing the numbers with spaces.
   • A1: The cell containing the data with spaces.
   • " ": A space character enclosed in quotes (what you are finding).
   • "": Two double quotes with nothing in between (what you are replacing the space with).
3. Press Enter. The new cell will display the number without any spaces.
4. Auto-fill this formula down the column for all relevant cells: select the cell with the formula and double-click the small square (fill handle) in the bottom-right corner of the cell boundary.
5. (Optional but Recommended) To replace the original data with the new clean data, copy the helper column, then right-click the original column's first cell and use Paste Special > Values. You can then delete the helper column.