Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 strings back to plain text. Supports UTF-8 and binary data.
How to Use the Base64 Encoder / Decoder
- Paste or type the text you want to encode or decode into the input field.
- Select whether you want to Encode (text to Base64) or Decode (Base64 to text).
- The conversion is performed instantly in your browser.
- Copy the result using the copy button or select and copy manually.
What is Base64 Encoding?
Base64 is a binary-to-text encoding scheme that represents binary data using a set of 64 ASCII characters (A-Z, a-z, 0-9, +, /). It was designed to safely transmit binary data over channels that only support text, such as email (MIME) and URLs. The encoding process takes every three bytes of input and converts them into four Base64 characters, which is why Base64-encoded data is approximately 33% larger than the original. Base64 is widely used in web development and security. Common use cases include embedding images directly in HTML or CSS via data URIs, encoding binary attachments in email, transmitting data in JSON or XML payloads, and encoding credentials in HTTP Basic Authentication headers. You will frequently encounter Base64 when working with APIs, JWTs, and cryptographic operations. It is important to understand that Base64 is an encoding, not encryption. It provides no confidentiality or security whatsoever. Anyone can decode a Base64 string instantly. Never use Base64 as a means to protect sensitive data. During penetration testing, Base64-encoded values in cookies, headers, or request parameters are among the first things to decode, as developers sometimes mistakenly use it to obscure sensitive information.
Frequently Asked Questions
No. Base64 is a reversible encoding scheme, not encryption. It provides zero security. Anyone can decode Base64 without a key. It is meant for data transport compatibility, not confidentiality. Never use Base64 to protect passwords, tokens, or sensitive information.
Base64 encodes every 3 bytes of input into 4 ASCII characters, resulting in approximately 33% size overhead. This happens because Base64 uses only 64 characters from the ASCII set, so it needs more characters to represent the same amount of binary data. Padding characters (=) are added when the input length is not a multiple of 3.
Standard Base64 uses the characters + and / which have special meanings in URLs. URL-safe Base64 replaces + with - and / with _ to avoid conflicts with URL encoding. You will encounter URL-safe Base64 in JWTs, data URIs used in query strings, and various API implementations.
Use Base64 when you need to embed binary data in text-based formats like JSON, XML, or HTML. Common scenarios include encoding images as data URIs, sending binary file content through REST APIs, encoding email attachments in MIME format, and encoding cryptographic keys or certificates in PEM format.