FormatExpress is a quick and easy-to-use beautifier. Just paste the input : the language is automatically detected, the input is formatted in a viewer with syntax highlighting and nodes navigation.
Disclaimer : I'm the developer of FormatExpress
Example of inputs:
JSON
{"maths":{"q1":{"question":"5 + 7 = ?","options":["10","11","12","13"],"answer":"12"},"q2":{"question":"12 - 8 = ?","options":["1","2","3","4"],"answer":"4"}}}
HTML
<html><body><h2>Text input fields</h2><form><label for="fname">First name:</label><br><input type="text" id="fname" name="fname" value="John"><br/><label for="lname">Last name:</label><br><input type="text" id="lname" name="lname" value="Doe"></form><p>Note that the form itself is not visible.</p><p>Also note that the default width of text input fields is 20 characters.</p></body></html>
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:small_orange_diamond: <a href="https://format-express.dev/"><b>FormatExpress</b></a> - online formatter and syntax highlighter for JSON, XML, HTML, CSS, SQL, etc.<br>