URL encoding converts characters into a format that can be transmitted over the Internet, for example when using [[URL parameters]]. URLs can only contain [[ASCII]] characters. URL encoding replaces unsafe ASCII characters with a "%" followed by two hexadecimal digits. URLs cannot contain spaces. URL encoding normally replaces a space with a plus (+) sign or with %20. [URLEncoder](https://www.urlencoder.io/) is an online tool for quickly encoding a URL. To learn more see the W3 Schools page [HTML URL Encoding Reference](https://www.w3schools.com/tags/ref_urlencode.ASP).