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How do I use the readonly attribute to make an input field read-only?
How do I use the readonly attribute to make an input field read-only?
Jun 22, 2025 am 12:52 AM
To make the input field read-only, use the readonly property. 1. Add readonly attribute to the input tag to achieve read-only effect; 2. readonly allows users to select and copy content and submit it with the form; 3. Unlike disabled, the latter is not submitted with the form and cannot gain focus; 4. The read-only state can be dynamically controlled through JavaScript, such as setting input.readOnly = true or false; 5. Pay attention to testing form submission behavior, accessibility and visual style when using it to improve user experience.
You can make an input field read-only by adding the readonly attribute to the <input> tag. This prevents users from modifying the value while still allowing them to select and copy it.
Basic usage of the readonly attribute
The readonly attribute is a boolean attribute, which means you don't need to assign a value to it. Just include it in the input element like this:
<input type="text" value="This is read-only" readonly>
When this is rendered in a browser, the input will look normal, but users won't be able to edit its content. However, they can still highlight and copy the text, and the value will be submitted with the form if applicable.
Here's what you should keep in mind:
- The input's value must be set using the
valueattribute forreadonlyto have any visible effect. - You can apply
readonlyto various input types, such astext,number,email, etc.
How readonly differences from disabled
Both readonly and disabled prevent users from editing an input, but there are important differences:
-
readonlyinputs submit their values ??with the form, whiledisabledinputs do not . -
readonlyfields can still receive focus (depend on browser behavior), butdisabledfields cannot. - Stylering: Browsers often apply default styles to
disabledelements (like grayed-out text), but not always forreadonly.
If you're building a form and need to display data that shouldn't be changed but still needs to be included when the form is submitted, use readonly . If you want to temporarily block interaction and also exclude the value from submission, go with disabled .
When to use JavaScript to toggle readonly
Sometimes you'll want to control whether an input is read-only based on user actions or other logic. In those cases, you can use JavaScript to dynamically add or remove the readonly attribute.
For example, you might have a checkbox that toggles edit mode:
<input type="checkbox" id="toggleEdit"> Allow editing
<br>
<input type="text" id="myInput" value="Initial value" readonly>
<script>
const checkbox = document.getElementById('toggleEdit');
const input = document.getElementById('myInput');
checkbox.addEventListener('change', function() {
input.readOnly = !this.checked;
});
</script>A few tips when working with JavaScript:
- Use
input.readOnly = trueto set it read-only, andinput.readOnly = falseto make it editable again. - Avoid using
removeAttribute('readonly')unless necessary — setting it tofalseis usually cleaner. - Be careful mixing
readonlyanddisabledvia JS; stick to one unless you have a specific reason.
Final notes
Using readonly is straightforward and effective when you need to show information in a form without letting users change it. It's especially useful for displaying calculated values, pre-filled data, or confirmation steps.
Just remember:
- Always test how your form behaves on submission.
- Consider accessibility — screen readers may announce read-only fields differently.
- Think about styling: some browsers don't visually distinguish
readonlyfields, so adding a custom class might help users understand the input isn't editable.
Basically that's it.
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