The HTML maxlength attribute
Quick answer
The HTML maxlength attribute sets the maximum number of characters the user can enter. It is used on the <input> and <textarea> elements.
Overview
The maxlength attribute limits the maximum character count. It is used on form controls such as <input>, <select> and <textarea>.
It is a form-control attribute: it configures how a control behaves, what it accepts, or its initial value, working alongside the control's <label> and parent <form>. Constraint attributes also feed the browser's built-in validation.
Syntax
<input maxlength="10">Values
| Value |
|---|
| A non-negative integer. |
Example
<input maxlength="10" placeholder="Max 10 chars" style="padding:8px;">Best practices
- Give every control a <label> so it has an accessible name.
- Treat client-side constraints as a convenience — always validate again on the server, since they can be bypassed.
- Choose the most specific input type so users get the right on-screen keyboard and built-in checks.
- Keep the submitted name and value meaningful for whatever processes the form.
Frequently asked questions
What does the maxlength attribute do?
Limits the maximum character count.
Are HTML form attributes enough for validation?
They give instant feedback, but client-side checks can be bypassed, so always validate on the server too.
Do form controls still need a label?
Yes. Every control needs a <label> for an accessible name, whatever attributes you set.
Which elements use the maxlength attribute?
It is an element-specific attribute, used on form controls such as <input>, <select> and <textarea>.