URL, Base64, HTML encoding/decoding
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Encoder/Decoder is a versatile online tool that converts text between various encoding formats including URL encoding, Base64, HTML entities, and Unicode escape sequences. Encoding transforms data into a safe, transmittable format, while decoding reverses the process back to human-readable text. This tool is essential for web developers, API engineers, and anyone who needs to handle encoded data in URLs, HTML documents, email systems, or data transmission protocols.
Select encoding method
Select the tab for the encoding method you want to use among URL, Base64, HTML Entity, or Unicode. A description of each method is provided to help you choose the appropriate encoding.
Enter text
Enter text to encode in the source area, or enter an encoded string to decode in the encoded-text area. Whichever side you edit, the other side updates automatically.
Check and copy results
Check the converted result and click the copy button to copy it to the clipboard. If needed, switch encoding tabs to convert the same text into another format.
URL encoding is needed when a URL contains Korean text, spaces, or special characters. When a browser sends a URL to a server, non-ASCII characters must be represented in %XX form. Query parameters containing special characters must also be encoded.
Base64 is an encoding method that converts binary data to ASCII strings. It is mainly used for sending email attachments (MIME), inserting images directly into HTML/CSS (Data URI), and including binary data in JSON. Size increases by approximately 33% compared to the original.
Characters such as <, >, &, " in HTML can be interpreted as tags or attributes, which can lead to security vulnerabilities (XSS). Converting to HTML entities allows these characters to be displayed safely, which is essential when displaying code snippets on web pages.
Unicode escapes (\uXXXX) are used to represent non-ASCII characters in source code. It is especially useful when you want to safely transmit multilingual characters such as Korean or emoji in JSON data, or when you want to avoid file encoding problems.
No. Encoding is converting the format of data so that anyone can decode it, while encryption is protecting the data using a secret key. Base64 encoding is not intended for security purposes and is not suitable for protecting sensitive data.