All of the below information is courtesy of W3 Schools and can be found here https://www.w3schools.com/tags/ref_attributes.asp
| Attribute | Tag | Description |
|---|---|---|
| accept | <input> | Specifies the types of files that the server accepts (only for type=”file”) |
| accept-charset | <form> | Specifies the character encodings that are to be used for the form submission |
| accesskey | Global Attribute | Specifies a shortcut key to activate/focus an element |
| action | <form> | Specifies where to send the form-data when a form is submitted |
| align | Not supported in HTML 5. | Specifies the alignment according to surrounding elements. Use CSS instead |
| alt |
<area>, <img>, <input> |
Specifies an alternate text when the original element fails to display |
| async | <script> | Specifies that the script is executed asynchronously (only for external scripts) |
| autocomplete |
<form>, <input> |
Specifies whether the <form> or the <input> element should have autocomplete enabled |
| autofocus |
<button>, <input>, <select>, <textarea> |
Specifies that the element should automatically get focus when the page loads |
| autoplay |
<audio>, <video> |
Specifies that the audio/video will start playing as soon as it is ready |
| bgcolor | Not supported in HTML 5. | Specifies the background color of an element. Use CSS instead |
| border | Not supported in HTML 5. | Specifies the width of the border of an element. Use CSS instead |
| charset |
<meta>, <script> |
Specifies the character encoding |
| checked | <input> | Specifies that an <input> element should be pre-selected when the page loads (for type=”checkbox” or type=”radio”) |
| cite |
<blockquote>, <del>, <ins>, <q> |
Specifies a URL which explains the quote/deleted/inserted text |
| class | Global Attribute | Specifies one or more classnames for an element (refers to a class in a style sheet) |
| color | Not supported in HTML 5. | Specifies the text color of an element. Use CSS instead |
| cols | <textarea> | Specifies the visible width of a text area |
| colspan |
<td>, <th> |
Specifies the number of columns a table cell should span |
| content | <meta> | Gives the value associated with the http-equiv or name attribute |
| contenteditable | Global Attributes | Specifies whether the content of an element is editable or not |
| controls |
<audi0>, <video>; |
Specifies that audio/video controls should be displayed (such as a play/pause button etc) |
| coords | <area> | Specifies the coordinates of the area |
| data | <object> | Specifies the URL of the resource to be used by the object |
| data-* | Global Attributes | Used to store custom data private to the page or application |
| datetime |
<del>, <ins>, <time> |
Specifies the date and time |
| default | <track> | Specifies that the track is to be enabled if the user’s preferences do not indicate that another track would be more appropriate |
| defer | <script> | Specifies that the script is executed when the page has finished parsing (only for external scripts) |
| dir | Global Attributes | Specifies the text direction for the content in an element |
| dirname |
<input>, <textarea>; |
Specifies that the text direction will be submitted |
| disabled |
<button>, <fieldset>, <input>, <optgroup>, <option>, <select>, <textarea>; |
Specifies that the specified element/group of elements should be disabled |
| download |
<a>, <area> |
Specifies that the target will be downloaded when a user clicks on the hyperlink |
| draggable | Global Attributes | Specifies whether an element is draggable or not |
| dropzone | Global Attributes | Specifies whether the dragged data is copied, moved, or linked, when dropped |
| enctype | <form> | Specifies how the form-data should be encoded when submitting it to the server (only for method=”post”) |
| for |
<label>, <output> |
Specifies which form element(s) a label/calculation is bound to |
| form |
<button>, <fieldset>, <input>, <label>, <meter>, <object>, <output>, <select>, <textarea> |
Specifies the name of the form the element belongs to |
| formaction |
<button>, <input> |
Specifies where to send the form-data when a form is submitted. Only for type=”submit” |
| headers |
<td>, <th> |
Specifies one or more headers cells a cell is related to |
| height |
<canvas>, <embed>, <iframe>, <img>, <input>, <object>, <video> |
Specifies the height of the element |
| hidden | Global Attributes | Specifies that an element is not yet, or is no longer, relevant |
| high | <meter> | Specifies the range that is considered to be a high value |
| href |
<a>, <area>, <base>, <link> |
Specifies the URL of the page the link goes to |
| hreflang |
<a>, <area>, <link> |
Specifies the language of the linked document |
| http-equiv | <meta> | Provides an HTTP header for the information/value of the content attribute |
| id | Global Attributes | Specifies a unique id for an element |
| ismap | <img> | Specifies an image as a server-side image-map |
| kind | <track> | Specifies the kind of text track |
| label |
<track>, <option>, <optgroup> |
Specifies the title of the text track |
| lang | Global Attributes | Specifies the language of the element’s content |
| list | <input> | Refers to a <datalist> element that contains pre-defined options for an <input> element |
| loop |
<audio>, <video> |
Specifies that the audio/video will start over again, every time it is finished |
| low | <meter> | Specifies the range that is considered to be a low value |
| max |
<input>, <meter>, <progress> |
Specifies the maximum value |
| maxlength |
<input>, <textarea> |
Specifies the maximum number of characters allowed in an element |
| media |
<a>, <area>, <link>, <source>, <style> |
Specifies what media/device the linked document is optimized for |
| method | <form> | Specifies the HTTP method to use when sending form-data |
| min |
<input>, <meter> |
Specifies a minimum value |
| multiple |
<input>, <select> |
Specifies that a user can enter more than one value |
| muted |
<video>, <audio> |
Specifies that the audio output of the video should be muted |
| name |
<button>, <fieldset>, <form>, <iframe>, <input>, <map>, <meta>, <object>, <output>, <param>, <select>, <textarea> |
Specifies the name of the element |
| novalidate | <form> | Specifies that the form should not be validated when submitted |
| onabort |
<audio>, <embed>, <img>, <object>, <video> |
Script to be run on abort |
| onafterprint | <body> | Script to be run after the document is printed |
| onbeforeprint | <body> | Script to be run before the document is printed |
| onbeforeunload | <body> | Script to be run when the document is about to be unloaded |
| onblur | All visible elements. | Script to be run when the element loses focus |
| oncanplay |
<audio>, <embed>, <object>, <video> |
Script to be run when a file is ready to start playing (when it has buffered enough to begin) |
| oncanplaythrough |
<audio>, <video> |
Script to be run when a file can be played all the way to the end without pausing for buffering |
| onchange | All visible elements. | Script to be run when the value of the element is changed |
| onclick | All visible elements. | Script to be run when the element is being clicked |
| oncontextmenu | All visible elements. | Script to be run when a context menu is triggered |
| oncopy | All visible elements. | Script to be run when the content of the element is being copied |
| oncuechange | <track> | Script to be run when the cue changes in a <track> element |
| oncut | All visible elements. | Script to be run when the content of the element is being cut |
| ondblclick | All visible elements. | Script to be run when the element is being double-clicked |
| ondrag | All visible elements. | Script to be run when the element is being dragged |
| ondragend | All visible elements. | Script to be run at the end of a drag operation |
| ondragenter | All visible elements. | Script to be run when an element has been dragged to a valid drop target |
| ondragleave | All visible elements. | Script to be run when an element leaves a valid drop target |
| ondragover | All visible elements. | Script to be run when an element is being dragged over a valid drop target |
| ondragstart | All visible elements. | Script to be run at the start of a drag operation |
| ondrop | All visible elements. | Script to be run when dragged element is being dropped |
| ondurationchange |
<audio>, <video> |
Script to be run when the length of the media changes |
| onemptied |
<audio>, <video> |
Script to be run when something bad happens and the file is suddenly unavailable (like unexpectedly disconnects) |
| onended |
<audio>, <video> |
Script to be run when the media has reach the end (a useful event for messages like “thanks for listening”) |
| onerror |
<audio>, <body>, <embed>, <img>, <object>, <script>, <style>, <video> |
Script to be run when an error occurs |
| onfocus | All visible elements. | Script to be run when the element gets focus |
| onhashchange | <body> | Script to be run when there has been changes to the anchor part of the a URL |
| oninput | All visible elements. | Script to be run when the element gets user input |
| oninvalid | All visible elements. | Script to be run when the element is invalid |
| onkeydown | All visible elements. | Script to be run when a user is pressing a key |
| onkeypress | All visible elements. | Script to be run when a user presses a key |
| onkeyup | All visible elements. | Script to be run when a user releases a key |
| onload |
<body>, <iframe>, <img>, <input>, <link>, <script>, <style> |
Script to be run when the element is finished loading |
| onloadeddata |
<audio>, <video> |
Script to be run when media data is loaded |
| onloadedmetadata |
<audio>, <video> |
Script to be run when meta data (like dimensions and duration) are loaded |
| onloadstart |
<audio>, <video> |
Script to be run just as the file begins to load before anything is actually loaded |
| onmousedown | All visible elements. | Script to be run when a mouse button is pressed down on an element |
| onmousemove | All visible elements. | Script to be run as long as the mouse pointer is moving over an element |
| onmouseout | All visible elements. | Script to be run when a mouse pointer moves out of an element |
| onmouseover | All visible elements. | Script to be run when a mouse pointer moves over an element |
| onmouseup | All visible elements. | Script to be run when a mouse button is released over an element |
| onmousewheel | All visible elements. | Script to be run when a mouse wheel is being scrolled over an element |
| onoffline | <body> | Script to be run when the browser starts to work offline |
| ononline | <body> | Script to be run when the browser starts to work online |
| onpagehide | <body> | Script to be run when a user navigates away from a page |
| onpageshow | <body> | Script to be run when a user navigates to a page |
| onpaste | All visible elements. | Script to be run when the user pastes some content in an element |
| onpause |
<audio>, <video> |
Script to be run when the media is paused either by the user or programmatically |
| onplay |
<audio>, <video> |
Script to be run when the media has started playing |
| onplaying |
<audio>, <video> |
Script to be run when the media has started playing |
| onpopstate | <body> | Script to be run when the window’s history changes. |
| onprogress |
<audio>, <video> |
Script to be run when the browser is in the process of getting the media data |
| onratechange |
<audio>, <video> |
Script to be run each time the playback rate changes (like when a user switches to a slow motion or fast forward mode). |
| onreset | <form> | Script to be run when a reset button in a form is clicked. |
| onresize | <body> | Script to be run when the browser window is being resized. |
| onscroll | All visible elements. | Script to be run when an element’s scrollbar is being scrolled |
| onsearch | <input> | Script to be run when the user writes something in a search field (for <input="search">) |
| onseeked |
<audio>, <video> |
Script to be run when the seeking attribute is set to false indicating that seeking has ended |
| onseeking |
<audio>, <video> |
Script to be run when the seeking attribute is set to true indicating that seeking is active |
| onselect | All visible elements. | Script to be run when the element gets selected |
| onstalled |
<audio>, <video> |
Script to be run when the browser is unable to fetch the media data for whatever reason |
| onstorage | <body> | Script to be run when a Web Storage area is updated |
| onsubmit | <form> | Script to be run when a form is submitted |
| onsuspend |
<audio>, <video> |
Script to be run when fetching the media data is stopped before it is completely loaded for whatever reason |
| ontimeupdate |
<audio>, <video> |
Script to be run when the playing position has changed (like when the user fast forwards to a different point in the media) |
| ontoggle | <details> | Script to be run when the user opens or closes the <details> element |
| onunload | <body> | Script to be run when a page has unloaded (or the browser window has been closed) |
| onvolumechange |
<audio>, <video> |
Script to be run each time the volume of a video/audio has been changed |
| onwaiting |
<audio>, <video> |
Script to be run when the media has paused but is expected to resume (like when the media pauses to buffer more data) |
| onwheel | All visible elements. | Script to be run when the mouse wheel rolls up or down over an element |
| open | <details> | Specifies that the details should be visible (open) to the user |
| optimum | <meter> | Specifies what value is the optimal value for the gauge |
| pattern | <input> | Specifies a regular expression that an <input> element’s value is checked against |
| placeholder |
<input>, <textarea> |
Specifies a short hint that describes the expected value of the element |
| poster | <video> | Specifies an image to be shown while the video is downloading, or until the user hits the play button |
| preload |
<audio>, <video> |
Specifies if and how the author thinks the audio/video should be loaded when the page loads |
| readonly |
<input>, <textarea> |
Specifies that the element is read-only |
| rel |
<a>, <area>, <link> |
Specifies the relationship between the current document and the linked document |
| required |
<input>, <select>, <textarea> |
Specifies that the element must be filled out before submitting the form |
| reversed | <ol> | Specifies that the list order should be descending (9,8,7…) |
| rows | <textarea> | Specifies the visible number of lines in a text area |
| rowspan |
<td>, <th> |
Specifies the number of rows a table cell should span |
| sandbox | <iframe> | Enables an extra set of restrictions for the content in an <iframe> |
| scope | <th> | Specifies whether a header cell is a header for a column, row, or group of columns or rows |
| selected | <option> | Specifies that an option should be pre-selected when the page loads |
| shape | <area> | Specifies the shape of the area |
| size |
<input>, <select> |
Specifies the width, in characters (for <input>) or specifies the number of visible options (for <select>) |
| sizes |
<img>, <link>, <source> |
Specifies the size of the linked resource |
| span |
<col>, <colgroup> |
Specifies the number of columns to span |
| spellcheck | Global Attributes | Specifies whether the element is to have its spelling and grammar checked or not |
| src |
<audio>, <embed>, <iframe>, <img>, <input>, <script>, <source>, <track>, <video> |
Specifies the URL of the media file |
| srcdoc | <iframe> | Specifies the HTML content of the page to show in the <iframe> |
| srclang | <track> | Specifies the language of the track text data (required if kind=”subtitles”) |
| srcset |
<img>, <source> |
Specifies the URL of the image to use in different situations |
| start | <ol> | Specifies the start value of an ordered list |
| step | <input> | Specifies the legal number intervals for an input field |
| style | Global Attributes | Specifies an inline CSS style for an element |
| tabindex | Global Attributes | Specifies the tabbing order of an element |
| target |
<a>, <area>, <base>, <form> |
Specifies the target for where to open the linked document or where to submit the form |
| title | Global Attributes | Specifies extra information about an element |
| translate | Global Attributes | Specifies whether the content of an element should be translated or not |
| type |
<button>, <embed>, <input>, <link>, <menu>, <object>, <script>, <source>, <style> |
Specifies the type of element |
| usemap |
<img>, <object> |
Specifies an image as a client-side image-map |
| value |
<button>, <input>, <li>, <option>, <meter>, <progress>, <param> |
Specifies the value of the element |
| width |
<canvas>, <embed>, <iframe>, <img>, <input>, <object>, <video> |
Specifies the width of the element |
| wrap | <textarea> | Specifies how the text in a text area is to be wrapped when submitted in a form |