URL Encode / Decode

Use the tool below to encode or decode data to and from a URL-compatible format. To ensure data safety, the encoding and decoding are performed within the browser without being sent across the internet.

URL encoding is a way to convert data into a format that can be safely included in a URL. URLs can only safely contain certain US-ASCII characters, which are limited to letters, numbers, and a few symbols. Data that contains other characters—such as spaces, punctuation, or non-English characters—needs to be encoded to ensure that browsers and servers interpret it correctly. URL encoding of these incompatible characters is achieved by replacing them with a percent sign (%) followed by two hexadecimal digits representing the character's byte value. For example, '^' is encoded as '%5E', and '<' is encoded as '%3C'. Unicode or other characters that occupy more than one byte are first converted into a sequence of bytes (typically using UTF-8) and then represented by a percent sign (%) followed by two hexadecimal digits for each byte. For example, 'Ω' is encoded as '%CE%A9', and 'β' is encoded as '%CE%B2'.

Because URL encoding uses the percent sign, it is also called percent-encoding. This encoding method is not limited to URLs; therefore, the term percent-encoding should be preferred.

The US-ASCII characters allowed in a URL are categorized as either reserved or unreserved. Reserved characters have special meanings in a URL, while unreserved characters do not. Based on RFC 3986, the reserved characters are:

!#$&'()*+,/:;=?@[]

and the unreserved characters are:

ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~

When reserved characters are used for their intended meanings in a URL, they do not need to be encoded. However, when used for other purposes, they need to be percent-encoded to distinguish them from their reserved meanings. For example, in the URL:

https://www.calculator.net/url-encode-decode.html?toprocess=encode%20%2F%20and%20%3F

the '/' is not encoded when serving as a path delimiter, and '?' is not encoded when indicating the start of the query string. However, they are encoded as '%2F' and '%3F' when used as part of the data in the value of 'encode / and ?' for the parameter 'toprocess'.

Unreserved characters can be used directly in URLs in all situations without being percent-encoded. Characters that are not in either category must be percent-encoded to be used safely in URLs.

There are numerous online and offline tools available to encode and decode data to and from a URL-safe format. Our tool above provides a convenient way to perform these conversions directly in the browser without sending data over the internet.