Base64 Encoder
Encode and decode text in Base64 instantly.
Online Base64 encoder and decoder: convert text and data instantly
Base64 is an encoding system that converts binary data into an ASCII text representation using a set of 64 characters (A-Z, a-z, 0-9, + and /). It was originally designed to transmit binary data through channels that only support text, such as the SMTP email protocol. Today, Base64 is widely used in web development to embed images directly in HTML/CSS (data URIs), transmit email attachments, encode authentication tokens in APIs, and store binary data in text formats like JSON or XML.
It is important to understand that Base64 is an encoding, not encryption. It provides no security or privacy: anyone can decode Base64 text without needing a key. Its purpose is to ensure that data is transmitted correctly between systems that could alter or reject binary characters.
Our tool encodes and decodes text with full support for Unicode characters, including accents and emojis. Processing is completely local in your browser, ensuring data privacy. The swap function lets you use encoded output as input for decoding and vice versa.
Frequently asked questions
Is Base64 encryption?
No, Base64 is not encryption or ciphering. It is simply an encoding that transforms data into a readable text format. Anyone can decode Base64 text without needing a password or key. If you need to protect sensitive data, you should use encryption algorithms like AES or RSA, not Base64.
Why is Base64 used in emails?
The SMTP email protocol was originally designed to transmit only 7-bit ASCII text. Email attachments (images, PDFs, documents) contain binary data that could be corrupted during transmission. Base64 converts this binary data into safe ASCII text, allowing attachments to arrive intact at their destination.
Does Base64 increase file size?
Yes, Base64 encoding increases data size by approximately 33%. This is because every 3 bytes of original data are represented with 4 ASCII characters. For this reason, it is not recommended to use Base64 for large files. In web development, it is advised to use Base64 data URIs only for small images (less than 10KB), such as icons or logos.
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