To comment out HTML blocks, use the <!-- --> syntax. This method allows developers to temporarily disable sections of HTML code without deleting them, ensuring the content is ignored by browsers but remains visible in the page source. It's useful for testing, collaboration, and A/B testing. However, it should not be used to hide sensitive information or in production builds. Remember 1) not to nest comments, 2) avoid using it for unfinished features, and 3) clean up before deployment.
You can't use traditional / / or // comments in HTML like you do in CSS or JavaScript, but there's a way to comment out blocks of HTML code properly. The correct method is using the <!-- --> syntax. Here’s how and when to use it.
Use <!-- --> to Comment Out HTML Blocks
In HTML, any content wrapped between <!-- and --> will be ignored by the browser. This works for single lines as well as multi-line blocks.
For example:
<!--
<div class="box">
<p>This content is commented out.</p>
</div>
-->This block won’t show up on the page, but it'll still be visible if someone views the page source. It’s especially useful when you’re testing or temporarily removing part of a layout without deleting it entirely.
A few things to remember:
- Make sure not to nest another
<!-- -->inside an already commented-out block. - Don’t use this to hide sensitive information — users can still see what’s commented out by viewing the source.
Why Not Just Delete the Code?
Sometimes developers just delete unused HTML elements while working on a layout. But commenting them out instead has advantages:
- You can quickly restore something that used to work if your new code breaks.
- It helps during team collaboration — others can see what was intentionally removed.
- Great for A/B testing different versions of a section without losing anything.
So instead of hitting “delete,” try commenting first — it's like keeping a backup right in your file.
When to Avoid Commented-Out HTML
There are cases where leaving commented HTML in your final code isn’t a good idea:
- In production builds — it adds unnecessary weight to your page.
- If you're hiding unfinished features — better to remove or use version control.
- For long-term storage of old layouts — use Git or notes instead.
It’s fine to keep during development, but clean it up before pushing live.
Basically, just wrap the HTML block with <!-- and -->. Works fast, easy to read, and handy while building pages.
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