How to use colgroup and col to style HTML table columns
Aug 02, 2025 pm 04:43 PMUse colgroup and col to efficiently apply styles to the entire column of HTML tables. 1. Define column groups through colgroups, col specifies each column style and put it in the header of the table; 2. Use span attributes to allow a single col to affect multiple columns; 3. It is recommended to use CSS classes instead of inline styles to improve maintainability; 4. Only some styles (such as width, background, alignment) take effect, padding or font size needs to be set through td/th; 5. Colgroup must be before tr, head, and tbody; 6. Multiple colgroups can be used to implement style control in different column areas; it is suitable for large or dynamic tables that require unified column width, background or border, and is an effective way to keep the style consistent and concise.
Using colgroup
and col
in HTML allows you to style entire columns of a table without having to apply styles to each individual cell. This is especially useful for large tables where consistency and maintainability matter. Here's how to use them effectively.

Understanding colgroup and col
The <colgroup></colgroup>
element defines a group of columns within a table, and the <col>
element specifies column properties for each column in the group. These elements are placed inside the <table> element, typically right after the opening <code><table> tag.<p> While <code>colgroup
and col
don't display anything on their own, they let you apply CSS styles (like width, background color, text alignment, etc.) to entire columns.

<table> <colgroup> <col span="1" style="background-color: #f0f0f0; width: 100px;"> <col span="2" style="background-color: #e0e0e0;"> </colgroup> <tr> <th>Product</th> <th>Price</th> <th>Stock</th> </tr> <tr> <td>Laptop</td> <td>$999</td> <td>12</td> </tr> </table>
In this example:
- The first
<col>
applies to the first column (Product). - The second
<col>
withspan="2"
applies to the next two columns (Price and Stock).
Styling columns with CSS classes
Instead of inline styles, you can use CSS classes for better separation of concerns.

<table class="styled-table"> <colgroup> <col class="product-col"> <col class="price-col"> <col class="stock-col"> </colgroup> <head> <tr> <th>Product</th> <th>Price</th> <th>Stock</th> </tr> </head> <tbody> <tr> <td>Laptop</td> <td>$999</td> <td>12</td> </tr> </tbody> </table>
.product-col { width: 150px; background-color: #f9f9f9; text-align: left; } .price-col { width: 100px; color: green; font-weight: bold; } .stock-col { width: 80px; text-align: center; }
This approach keeps your styles in CSS and makes them reusable across multiple tables.
Key points and limitations
- Only certain styles work : You can apply width, border, visibility, background, and text alignment via
col
andcolgroup
. Other styles (like padding or font size) may not apply as expected because columns are not direct containers of content. - Structure matters :
colgroup
must come before any table rows (tr
,thead
,tbody
). - Spanning columns : Use the
span
attribute on<col>
to style multiple consecutive columns at once. - Multiple colgroups : You can have more than one
colgroup
, but only one can have aspan
unless you define each column individually.
Example with multiple colgroup
s:
<colgroup span="2" style="background: #ddd;"></colgroup> <colgroup span="1" style="background: #ffcccc;"></colgroup>
This applies one style to the first two columns and another to the third.
When to use colgroup and col
Use colgroup
and col
when:
- You want consistent column widths.
- You need to set background colors or borders for entire columns.
- You're working with dynamic or large tables and want to avoid repeating styles in every cell.
It's not ideal for complex styling (like padding or margins on cells), so combine it with regular CSS on td
and th
when needed.
Basically, colgroup
and col
give you a clean, efficient way to manage column-level styling in HTML tables—simple but easy to overlook.
The above is the detailed content of How to use colgroup and col to style HTML table columns. For more information, please follow other related articles on the PHP Chinese website!

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