# Bad value “1” for attribute “multiple” on element “select”.

> Canonical HTML version: https://rocketvalidator.com/html-validation/bad-value-1-for-attribute-multiple-on-element-select
> Attribution: Rocket Validator (https://rocketvalidator.com)
> License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

The `multiple` attribute on the `<select>` element is a boolean attribute and does not accept a value like `"1"`.

On a `<select>`, `multiple` lets the user pick more than one option. Like every boolean attribute in HTML, its meaning comes from whether it is present, not from what you set it to. Writing `multiple="1"` makes the W3C validator complain because `"1"` is not one of the values the spec allows.

A boolean attribute can only appear in three forms: the name on its own (`multiple`), an empty string (`multiple=""`), or the name repeated as the value (`multiple="multiple"`). Values such as `"1"`, `"true"`, or `"yes"` look reasonable but none of them are valid.

## Invalid example

```html
<select name="toppings" multiple="1">
  <option value="cheese">Cheese</option>
  <option value="mushrooms">Mushrooms</option>
  <option value="olives">Olives</option>
</select>
```

## Valid example

```html
<select name="toppings" multiple>
  <option value="cheese">Cheese</option>
  <option value="mushrooms">Mushrooms</option>
  <option value="olives">Olives</option>
</select>
```

Dropping the value and keeping just `multiple` is the clearest way to write it.