Void Elements List Checker

Checks parsed HTML element names against the 13 current void elements; names are ASCII case insensitive. This does not parse markup or classify obsolete elements.

Description

Void HTML elements have no child content and no end tag in HTML syntax.

Void HTML elements have no child content and no end tag in HTML syntax. Recognizing their parsed names helps distinguish them from ordinary container elements.^[1]

The tool returns isVoid, voidCount. The fields describe the supplied local pattern or effective state, or contain the formatted markup shown below.

When to use Void Elements List Checker

Use this for the following task: Checks parsed HTML element names against the 13 current void elements; names are ASCII case insensitive. This does not parse markup or classify obsolete elements. Provide the requested local fields extracted from the relevant element or attribute.

How to use Void Elements List Checker and understand its results

Prepare the parsed element names, attribute values or direct element-child lists requested below. Keep attribute presence separate from its value.
Enter names according to the field table, then run the tool.
Read isVoid, voidCount. Check the effective state, recognized-token flags or generated markup against the rules below.
Correct any reported local mismatch and check the resulting markup in its intended document and browser context.

Input field	Meaning	Value type and bounds	Requirement
names	Names	list of string; minimum entries 0; maximum entries 10000; each entry: maximum text length 10000	Required

Supply parsed element names. Fold ASCII case, return membership flags for the 13-name vocabulary and count matches.

void names: area, base, br, col, embed, hr, img, input, link, meta, source, track, wbr

The symbols and boundary conditions refer to the supplied fields and the implementation described above.

Output field	Meaning	Value type
isVoid	Is Void	list of boolean
voidCount	Void Count	integer

json

{
  "input": {
    "names": [
      "IMG",
      "div",
      "br",
      "source"
    ]
  },
  "output": {
    "isVoid": [
      true,
      false,
      true,
      true
    ],
    "voidCount": 3
  }
}

Limitations and assumptions

Supply parsed names without angle brackets. Matching folds ASCII uppercase letters without trimming surrounding whitespace. This does not parse markup, validate end tags or classify obsolete elements or foreign SVG/XML syntax.

The tool does not fetch a page, run a browser or validate an entire HTML document. Malformed tool requests produce input errors; valid requests can still report unrecognized values or failed local checks.

Alternative or Complementary methods

Choose Boolean Attributes List Lookup when you need its operation: Looks up current standard HTML boolean attribute names, independent of their element applicability. Enumerated hidden, draggable and contenteditable are excluded. Choose hr Thematic Break Semantics for the complementary operation: Identifies hr as a paragraph-level thematic break in a list of parsed HTML element names. A rendered horizontal line alone does not establish these semantics.

Background reference: HTML Standard: Void Elements List Checker.

References

HTML Standard: Void Elements List Checker — WHATWG

Similar or alternative tools

Boolean Attributes List Lookup
Looks up current standard HTML boolean attribute names, independent of their element applicability. Enumerated hidden, draggable and contenteditable are excluded.
hr Thematic Break Semantics
Identifies hr as a paragraph-level thematic break in a list of parsed HTML element names. A rendered horizontal line alone does not establish these semantics.