By Steven Melendez Updated January 16, 2019
In Microsoft Excel and other popular modern spreadsheet programs, text and numbers are displayed in a rectangular grid of cells. Generally, every cell in a row or column has the same size, so you can't adjust the size of a cell individually without affecting the others in its same row or column. You can merge adjacent cells to create larger compound cells, however, and you can set rows and columns to automatically adjust to fit text.
Change Cell Size in Excel
You can change the height of every cell in a row or the width of every cell in a column in Excel.
To set the Excel row height for a particular row, click a cell in that row, then click the "Home" on the ribbon menu. In the "Cells" submenu, click "Format." Under "Cell Size," click "Row Height" and enter the value you want, then click "OK." Experiment with different row heights to find one to make your row look nice while being easily legible.
To change the width of a column in Excel, click a cell in the column and click "Home" on the ribbon menu. Under "Cells," click "Format" and click "Column Width" under "Cell Size." Enter the desired width and click "OK." Experiment with appropriate column widths to find one that works for your needs.
Tweaking Sizes With the Mouse
You can also quickly adjust the size of a row or column using your computer's mouse.
Click the boundary at the bottom of a row and drag it up or down to tweak the row's height. Similarly, you can drag the boundary at the right of a column to adjust the width to whatever width you want.
Using AutoFit in Excel
If you don't want to set the height or width of rows or columns in Excel, you can use Excel's AutoFit feature to automatically contract or expand cells in Excel to fit their contents. This will ensure that everything in the cells is visible, which can help avoid misunderstandings when reading the spreadsheet.
To use AutoFit, click a cell in the row or column you want to change. Within the ribbon menu, click "Home." Under "Cells," click the "Format" button. Under "Cell Size" click "AutoFit Column Width" or "AutoFit Row Height" as desired.
If you want to apply AutoFit to an entire spreadsheet, click "Select All" in the "Edit" menu. Then either use the "Format" menu with all cells selected or double click a boundary between two columns to AutoFit column widths or a boundary between two rows to AutoFit column heights.
Note that spreadsheet cells can grow to unwieldy sizes if they have a lot of content in them, so this isn't always the best choice if you have a few cells with a lot of content in them. You may wish to turn AutoFit off for rows or columns with especially large cells.
Merging Multiple Cells
You can merge cells in Excel to create a combined cell that spans multiple columns or rows.
To do so, select the cells you want to merge using your mouse. Then, click the "Home" tab in the ribbon menu. Click "Merge & Center" in the menu to merge the cells and center the text within the combined cell. Note that only the content from the top left merged cell will be preserved, so back up any other content you want to save before merging cells.
If you later want to unmerge the cells, you can do this using the same menu. Click the merged cell, then click the "Home" tab in the ribbon menu. Click the drop-down arrow next to "Merge & Center" in the menu and click "Unmerge Cells." You can't unmerge a normal cell that wasn't created through an earlier merge operation.
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