Base64 Encoder / Decoder
A free, secure tool to encode text to Base64 and decode Base64 to text. All processing happens in your browser, ensuring your data's privacy. Ideal for developers working with Data URIs, APIs, and text-based data transmission.
What is Base64 Encoding? A Developer's Guide
From Binary Data to ASCII Text: Understanding the Web's Universal Translator
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. Its primary purpose is to ensure that data remains intact without modification during transport through text-only systems, such as email (MIME) or when embedding data in text-based formats like HTML, CSS, or JSON.
This tool provides a simple, secure, and instant way to work with Base64 encoding. Because it operates entirely within your browser, your data is never sent to a server, guaranteeing its privacy. This makes our Base64 converter safe to use for any type of string data, including sensitive API keys, configuration variables, or other credentials that should not be exposed.
How to Use This Secure Base64 Converter
A simple step-by-step guide to encoding and decoding your data.
- Input Your Data: Paste the text you wish to encode or the Base64 string you want to decode into the "Input" field.
- Choose Your Action:
- Click Encode to Base64 to convert your text into a Base64 string. Our tool correctly handles Unicode and UTF-8 characters.
- Click Decode from Base64 to convert a Base64 string back to its original form. The tool will show an error if the string is invalid.
- Copy the Result: The output will appear instantly. Use the "Copy" button to copy the result to your clipboard for use in your project.
Your Privacy is Guaranteed
Technical Deep Dive: How Does Base64 Work?
The Base64 encoding process is a clever bit of data manipulation designed for compatibility. At its core, it takes a stream of binary data and translates it into a limited set of 64 common ASCII characters that are safe to transmit over any text-based system. The standard character set includes A-Z, a-z, 0-9, and the '+' and '/' symbols. The '=' character is also used for padding.
The process works by taking 3 bytes (a total of 24 bits) of the input data at a time. This 24-bit block is then divided into four 6-bit chunks. Since 26 equals 64, each 6-bit chunk can be represented by one of the 64 characters in the Base64 alphabet. For example, the binary sequence `000000` maps to 'A', `000001` maps to 'B', and so on. This continues until all the input data has been processed.
If the final block of input data is less than 3 bytes long, padding is added. If there's one byte left (8 bits), it's treated as a 6-bit chunk followed by two zero bits, and two padding characters ('==') are added to the output. If two bytes are left (16 bits), they are treated as two 6-bit chunks and one 4-bit chunk followed by two zero bits, and one padding character ('=') is added. This ensures the output string's length is always a multiple of 4. This conversion from 3 bytes to 4 characters is why Base64-encoded data is approximately 33% larger than the original.
Related Tools & Reading
Explore other encoding tools and expand your knowledge.
If you need to encode characters for use in a URL, our URL Encoder / Decoder is the correct tool for the job, as it handles special URL characters differently.
Frequently Asked Questions
Frequently Asked Questions
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