Here you will find a summary of all the metrics used in their respective custom metrics file
almanac.js metrics
Whether the page contains any instances of <script type=module>.
1 if true, 0 if false
Whether the page contains any instances of <script nomodule>
1 if true, 0 if false
A JSON array of nodes used in the element.
Example response:
{
"total": 28,
"nodes": [
{
"tagName": "link",
"rel": "stylesheet",
"href": "/static/css/normalize.css?v=112272e51c80ffe5bd01becd2ce7d656"
},
{
"tagName": "link",
"rel": "preload",
"href": "/static/css/normalize.css?v=112272e51c80ffe5bd01becd2ce7d656",
"as": "style"
},
...
],
"attribute_usage_count": {
"rel": 28,
"href": 28,
"as": 8,
"type": 5,
"crossorigin": 5,
"hreflang": 14
}
}A JSON array of prioritized nodes and their key/value attributes. Checks for the importance attribute in <link> <img> <script> or <iframe>.
Example response:
{
"total": 28,
"nodes": [
{
"tagName": "link",
"rel": "...",
"href": "...",
"importance": "low",
},
{
"tagName": "img",
"href": "...",
"importance": "low",
},
...
],
"attribute_usage_count": {
"rel": 28,
"href": 28,
"as": 8,
"type": 5,
"importance": 32
}
}A JSON array of <meta> nodes within the <head> element.
Example response:
"meta-nodes": {
"total": 16,
"nodes": [
{
"tagName": "meta",
"charset": "UTF-8"
},
{
"tagName": "meta",
"name": "viewport",
"content": "width=device-width, initial-scale=1"
},
{
"tagName": "meta",
"name": "description",
"content": "The Web Almanac is an annual state of the web report combining the expertise of the web community with the data and trends of the HTTP Archive."
},
...
],
"attribute_usage_count": {
"charset": 1,
"name": 8,
"content": 15,
"property": 7
}
}DEPRECATED. See wpt_bodies.js
Extracts schema.org elements and finds all @context and @type usage.
Example response:
[
"WebPage",
"ImageObject",
"Organization",
"Person",
"schema.org/Article",
"ListItem",
"schema.org/BreadcrumbList"
]DEPRECATED. See wpt_bodies.js
Finds the total number of internal, external and hash links.
We also count earlyHash and navigateHash. If a hash link is found within the first three <a> elements, we also count it as a earlyHash. This is primarily used to discover skip links. Otherwise the has link is counted as a navigateHash
Example response:
{
"internal": 108,
"external": 12,
"hash": 1,
"navigateHash": 0,
"earlyHash": 1
}Counts the total number of h1, h2, h3 and h4 elements. And the total number of words used in each (split by a space). If none exist, the value for both titleWords and titleElements is -1
Example response:
{
"titleWords": 15,
"titleElements": 6
}Counts the total number of textual elements, and words are on the page. All script and and style elements are excluded. If an element is found to contain under 3 words, it is skipped over as well.
Example response:
{
"wordsCount": 391,
"wordElements": 36
}Captures all the <input> and <select> elements on the page.
Example response:
{
"total": 6,
"nodes": [
{
"tagName": "select",
"id": "table-of-contents-switcher-mobile"
},
{
"tagName": "select",
"id": "year-switcher-mobile"
},
{
"tagName": "select",
"id": "language-switcher-mobile"
},
{
"tagName": "select",
"id": "table-of-contents-switcher-mobile-footer"
},
{
"tagName": "select",
"id": "year-switcher-mobile-footer"
},
{
"tagName": "select",
"id": "language-switcher-mobile-footer"
}
],
"attribute_usage_count": {
"id": 6,
"data-label": 2
}
}Lists all of the different protocols used in <a href> elements, along with their frequency
Example response:
{
"https": 2,
"http": 1,
"tel": 1,
"javascript": 1
}Detects if the first child of <head> is a Google Fonts <link>. 1 if true, 0 if false.
Counts the number of <link> and <script> elements using the subresource integrity attribute.
Example response:
{
"link": 3,
"script": 0
}A JSON array of nodes with a tabindex and their key/value attributes.
To save space, only the tagName and tabindex are reported for each node. attribute_usage_count can be used to see how many times each attribute was used.
Example response:
{
"total": 150,
"nodes": [
{
"tagName": "a",
"tabindex": "0"
},
{
"tagName": "a",
"tabindex": "0"
},
{
"tagName": "select",
"tabindex": "0"
},
{
"tagName": "a",
"tabindex": "-1"
},
...
],
"attribute_usage_count": {
"id": 13,
"tabindex": 150,
"class": 148,
"aria-describedby": 2,
"data-nav-digest": 1,
"data-nav-selected": 1,
"name": 2,
"style": 5,
"title": 43,
"type": 2,
"value": 2,
"autocomplete": 1,
"placeholder": 1,
"dir": 1,
"aria-label": 21,
"href": 50,
"data-nav-ref": 1,
"data-nav-role": 1,
"data-ux-jq-mouseenter": 3,
"data-csa-c-type": 31,
"data-csa-c-slot-id": 31,
"data-csa-c-content-id": 30,
"data-csa-c-id": 31,
"aria-disabled": 4,
"aria-hidden": 15,
"data-elementid": 2,
"playsinline": 1,
"role": 90,
"lang": 1,
"aria-valuenow": 2,
"aria-valuemin": 2,
"aria-valuemax": 2,
"aria-live": 1,
"aria-valuetext": 1,
"aria-checked": 1,
"data-testid": 1,
"data-id": 83
}
}Counts the number of <a> or <button> elements only containing an icon. Clickables containing 1-char text are also assumed to be icons.
The response is an integer of how many were on the site. 0 if none.
A string containing the entire content property of the meta elements matching <meta name="generator" content="AMP Plugin...">. If this <meta> tag was not detected, this value is null
The total number of <svg>'s used, their combined content length, and all the attributes used on the <svg> elements (not any of their child elements).
Example response:
{
"total": 1,
"content_lengths": [
944
],
"attribute_usage_count": {
"width": 1,
"height": 1,
"viewbox": 1,
"version": 1,
"xmlns": 1,
"xmlns:xlink": 1,
"data-testid": 1,
"role": 1,
"aria-labelledby": 1
}
}Stats of <img>, <source> and <picture> elements.
Note: In alt_lengths, -1 is used to represent images with no alt tag at all. Empty alt tags have a value of 0
Example response:
{
"pictures": {
"total": 0,
"nodes": [],
"attribute_usage_count": {}
},
"imgs": {
"total": 217,
"nodes": [
{
"tagName": "img"
},
{
"tagName": "img"
},
{
"tagName": "img"
},
{
"tagName": "img"
},
...
],
"attribute_usage_count": {
"src": 216,
"style": 2,
"alt": 215,
"height": 155,
"width": 6,
"data-a-hires": 213,
"class": 194,
"id": 1,
"data-bind": 1
}
},
"sources": {
"total": 0,
"nodes": [],
"attribute_usage_count": {}
},
"total_with_srcset": 0,
"total_with_sizes": 0,
"total_pictures_with_img": 0,
"sizes_values": [],
"loading_values": [],
"alt_lengths": [
0,
76,
139,
82,
30,
45,
13,
-1,
-1,
0,
...
]
}Stats of <video> and <track> elements.
total_with_track contains the total number of <video> elements had at least one <track> element
Example response:
{
"total": 1,
"nodes": [
{
"tagName": "video",
"poster": "https://images-na.ssl-images-amazon.com/.../slate.jpg"
}
],
"attribute_usage_count": {
"class": 1,
"webkit-playsinline": 1,
"playsinline": 1,
"poster": 1,
"src": 1
},
"total_with_track": 1,
"tracks": {
"total": 0,
"nodes": [],
"attribute_usage_count": {}
}
}Stats about <iframe> elements
Example response:
{
"iframes": {
"total": 1,
"nodes": [
{
"tagName": "iframe",
"id": "DAsis",
"src": "//s.amazon-adsystem.com/...",
"width": "1",
"height": "1",
"frameborder": "0",
"marginwidth": "0",
"marginheight": "0",
"scrolling": "no",
"o46fdkdxl": ""
}
],
"attribute_usage_count": {
"id": 1,
"src": 1,
"width": 1,
"height": 1,
"frameborder": 1,
"marginwidth": 1,
"marginheight": 1,
"scrolling": 1,
"o46fdkdxl": 1
}
}
}Stats about <script> elements.
Example response:
{
"total": 8,
"nodes": [
{
"tagName": "script",
"type": "application/ld+json"
},
{
"tagName": "script",
"type": "application/ld+json"
},
{
"tagName": "script",
"nonce": ""
},
{
"tagName": "script",
"async": "",
"src": "/static/js/almanac.js?v=a048e74d864cb071cf57bbec86f4cfdc"
},
{
"tagName": "script",
"defer": "",
"src": "/static/js/send-web-vitals.js?v=f176ee2628e8a2a549a6f5f3e122ee22"
},
...
],
"attribute_usage_count": {
"type": 2,
"nonce": 2,
"async": 2,
"src": 4,
"defer": 2
}
}The total number of nodes using the role attribute, and how often each value of role was used
Example response:
{
"total": 269,
"usage_and_count": {
"navigation": 2,
"search": 1,
"button": 87,
"main": 1,
"list": 8,
"listitem": 140,
"presentation": 18,
"region": 1,
"slider": 2,
"menu": 3,
"menuitemradio": 1,
"dialog": 1,
"document": 1,
"image": 1,
"tooltip": 1,
"complementary": 1
}
}What order the headings levels are on the page. Can be used to determine if there were heading levels skipped
Example response:
[
1,
2,
2,
3,
2,
2
]What accesskey or aria-keyshortcuts values are used.
Example response:
{
"total_with_aria_shortcut": 2,
"total_with_accesskey": 1,
"aria_shortcut_values": ["Alt+Shift+M", "Alt+Shift+B"],
"accesskey_values": ["s"]
}The attributes used across the entire page, and how many times each was used.
Example response:
{
"lang": 51,
"charset": 1,
"name": 8,
"content": 15,
"rel": 30,
"href": 150,
"as": 9,
"type": 14,
"crossorigin": 5,
"property": 7,
"hreflang": 15,
"class": 171,
"xmlns": 1,
"width": 15,
"height": 15,
"display": 1,
"id": 41,
"viewBox": 9,
"d": 9,
"fill": 11,
"fill-rule": 1,
"clip-rule": 1,
"cx": 2,
"cy": 2,
"r": 1,
"stroke-width": 3,
"stroke-miterlimit": 3,
"stroke": 3,
"rx": 1,
"ry": 1,
"aria-label": 10,
"aria-expanded": 7,
"data-event": 4,
"data-label": 4,
"aria-labelledby": 10,
"data-open-text": 1,
"data-close-text": 1,
"for": 6,
"selected": 6,
"disabled": 4,
"value": 88,
"aria-hidden": 3,
"role": 9,
"xmlns:xlink": 9,
"xlink:href": 9,
"nonce": 2,
"x": 1,
"y": 1,
"src": 9,
"alt": 5,
"loading": 4,
"async": 2,
"defer": 2
}The attributes used on the <body> node.
Note: tagName is not an attribute used on the element, but what type of node the element is
Example response:
{
"tagName": "body",
"class": "year-2020"
}The attributes used on the <html> node.
Note: tagName is not an attribute used on the element, but what type of node the element is
Example response:
{
"tagName": "html",
"lang": "en-us",
"class": "...",
"data-useragent": "...",
"data-platform": "..."
}The <title> tag value and its length
Example response:
{
"value": "The 2020 Web Almanac",
"length": 20
}An array containing the length of every <h1> on the page
Example response:
[5, 12, 11]Images.js metrics
A JSON array of <img> elements on the page.
Sample response:
{
"url": "https://placekitten.com/401/401",
"width": 401,
"height": 401,
"naturalWidth": 401,
"naturalHeight": 401,
"loading": "lazy",
"inViewport": true
}