<output>

HTML <output> Tag

The <output> tag is one of the HTML5 elements. It defines a place for representing the result of a calculation performed by a script or user’s interaction with a form element (<form> tag). The <output> tag is designed for complex calculations, like the results of an exchange rate conversion.

Calculating with the <output> tag

Calculating with the <output> tag

In order to use the <output>, some basic knowledge of JavaScript is required. Define an <input> type of number to inform the form that the user is entering integers. If the user enters another information, the <output> form returns NaN , that means not a number. Nowadays, <output> is not supported internationally.

Syntax

Syntax

The <output> tag comes in pairs. The content is written between the opening (<output>) and closing (</output>) tags.

Example of the HTML <output> tag with two <form> elements:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
  </head>
  <body>
    <form oninput="x.value=parseInt(a.value)+parseInt(b.value)">0
      <input type="range" id="a" value="50">100 +
      <input type="number" id="b" value="25"> =
      <output name="x" for="a b"></output>
    </form>
    <p>Multiplication:</p>
    <form oninput="d.value = e.valueAsNumber * f.valueAsNumber">
      <input type="number" id="e"> *
      <input type="number" id="f"> =
      <output name="d" for="e f"> </output>
    </form>
  </body>
</html>

Result

Example of the HTML <output> tag with one <form> element:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      div {
        display: flex;
        align-items: center;
        margin-bottom: 20px;
      }
    </style>
  </head>
  <body>
    <form oninput="result.value=parseInt(a.value)+parseInt(b.value)+parseInt(c.value)">
      <div>
        <input type="number" name="a" value="30" /> +
        <input type="range" name="b" value="0" /> +
        <input type="number" name="c" value="25" />
      </div>
      The result is:
      <output name="result"></output>
    </form>
  </body>
</html>

Attributes

Attributes

AttributeValueDescription
forelement_idDefines the id of an element/elements, specifying the connection between the calculation result and elements, which are used in the calculation.
formform_idDefines one or more forms, which the output element belongs to.
namenameDefines the name of the element.

The <output> tag supports the Global Attributes and the Event Attributes.



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