When using worksheets, you may wish to visually merge multiple cells into one cell.
For instance, while formatting the header region you may wish a single title to be centered across your whole table, or you may merge rows in a Gantt chart to display time across multiple cells, or you might merge cells where there is duplicate data.
How to Merge Cells
Begin by selecting the cells you want to merge. From the top toolbar, click the Merge icon and select your merge option from the dropdown.
You can also access these options via Format > Merge cells in the document menu.
How to Access the Document Menu
To access the document menu,
- Open the document dropdown by clicking the arrow to the right of the document name
- Select "Menu..." from the dropdown
Spreadsheet.com supports three merge options: Merge All, Merge horizontally, and Merge vertically. Merged cells can also be unmerged, which we'll cover later in this article.
Looking for a quicker way to merge cells? Try the merge keyboard shortcut (Ctrl + M).
The three merge options work as follows:
By default, clicking merge cells will merge the top-leftmost value across all selected cells. If you merge cells with values in multiple cells, only the top-leftmost value will remain.
Merging horizontally will merge the leftmost value in each row across all selected rows and merging vertically will merge the topmost value in each column across all selected columns.
When you merge cells where some data will be lost, Spreadsheet.com will warn you that only the top-leftmost value will remain.
How to Undo Lost Data from Merge
Merging cells may delete data from your worksheet. To return the data, you will have to undo the merge and then move the data before merging the cells again. To undo an action, either use the keyboard shortcut Ctrl + Z, select the Undo button 
in the Toolbar, or choose the Undo option in the Edit menu.
How to Unmerge Cells
Cells that have been merged can also be unmerged. However, unmerging cells does not restore the data previously in those cells.
With the previously merged cells selected, you can access the "Unmerge" option from the Merge icon in the toolbar or the Format menu in the workbook menu.
It is not possible to unmerge only a part of a merged range. However, you can unmerge all the cells and then remerge those cells you want to stay merged.
Formulas, Comments, and Data Combination Functions
Formulas
Because merging cells only preserves the top-leftmost cell (or leftmost or topmost if merging horizontally or vertically), formulas that use values in merged cells may break. Any formulas impacted by the merge action will be pointed at new cells, or the values in the merged cells will need to be restored (using Undo) and cut and pasted into a different cell. See our Formula readjustment article for more details.
Comments
Similarly, when you merge cells, only the cell comments of the top-leftmost cell appear in the merged cell. The cell messages of all other merged cells can still be seen in the row channel and will restore if you unmerge the cells.
Data Combination Functions
Merging cells does not merge the data in the cells. If you want to combine data from multiple cells into a single cell, you can choose from text functions such as JOIN, CONCATENATE, or others.
Merging cells is a great way to format your data, particularly the data in the header region. For more advanced formatting techniques, check out our articles on assigning formatting with formulas.