Base64 Encoder/Decoder Tool - Online & Free
Real-time Base64 encode and decode online tool. Support text and file conversion with instant feedback. Secure, fast, and free.
Online Base64 Encoder and Decoder
Welcome to the ultimate Online Base64 Encoder and Decoder. This simple yet powerful tool allows you to convert text to Base64 or decode Base64 strings back to human-readable text instantly.
Base64 encoding schemes are essential when encoding binary data for storage or transfer over media designed for text (like HTTP or SMTP).
Advanced Configuration Options
Character Set Selection
When dealing with textual data, specifying the correct character set (charset) is crucial. While UTF-8 is the standard, legacy systems may use ASCII, ISO-8859-1, or others.
Decode Each Line Separately
Encoded data often appears as a continuous block of text. However, if you have multiple independent Base64 strings separated by newlines, enable this option.
Live Conversion Mode
Enable Live Mode for instant results as you type. This mode performs Base64 conversion locally in your browser using JavaScript, ensuring zero latency.
Secure and Private
Your privacy is our priority. All communications use secure SSL encrypted connections (HTTPS). We never inspect, store, or share your submitted data.
Completely Free Online Tool
Our Base64 tool is 100% free to use. No software installation, registrations, or subscriptions required.
Design Principles
A Base64 index table consists of 64 characters chosen to be both common to most encodings and printable. This minimizes the risk of data modification by systems like email servers.
What is Base64 Encoding?
Base64 is a group of binary-to-text encoding schemes that represent binary data in an ASCII string format by translating it into a radix-64 representation.
Base64 Encoding Example
Consider this quote from Thomas Hobbes's Leviathan:
"Man is distinguished, not only by his reason, but ..."
When encoded into MIME Base64, this ASCII sequence becomes:
TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sIGJ1dCAuLi4=How it works: The word "Man" is encoded as "TWFu". In ASCII, "M", "a", "n" are bytes 77, 97, 110. Their binary representations are joined and divided into 6-bit groups.
| Text content | M | a | n | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ASCII Value | 77 | 97 | 110 | |||||||||||||||||||||
| Binary | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 |
| Index | 19 | 22 | 5 | 46 | ||||||||||||||||||||
| Base64 | T | W | F | u | ||||||||||||||||||||
As shown, Base64 encoding converts 3 bytes of input data (24 bits) into 4 Base64 characters (6 bits each), expanding the data size by approximately 33%.