How can I escape a single quote?

You could use HTML entities:

' for '

" for "

...

For more, you can take a look at Character entity references in HTML.

You can use ' (which is iffy in IE) or ' (which should work everywhere). For a comprehensive list, see the W3C HTML5 Named Character References or the HTML entities table on WebPlatform.org.

As you’re in the context of HTML, you need to use HTML to represent that character. And for HTML you need to use a numeric character reference ' (' hexadecimal):

<input type='text' id='abc' value='hel&#39;lo'>

Represent it as a text entity (ASCII 39):

<input type='text' id='abc' value='hel&#39;lo'>

Probably the easiest way:

<input type='text' id='abc' value="hel'lo">

If for some reason you cannot escape the apostrophe character and you can't change it into a HTML entity (as it was in my case for a specific Vue.js property) you can use replace to change it into different apostrophe character from the UTF-8 characters set, for instance:

ʼ - U+02BC
’ - U+2019

I personally find the named HTML entities easier to remember:

' for ' (known as single quote or apostrophe, Unicode character U+0027)

" for " (known as double quote or quotation mark, Unicode character U+0022)

Demo:

'
"

You could try using: ‘

use javascript inbuild functions escape and unescape

for example

var escapedData = escape("hel'lo");   
output = "%27hel%27lo%27" which can be used in the attribute.

again to read the value from the attr

var unescapedData = unescape("%27hel%27lo%27")
output = "'hel'lo'"

This will be helpful if you have huge json stringify data to be used in the attribute