Base64 Encoder / Decoder
Encode text or files to Base64, or decode Base64 strings
Input Text
0 characters
Output
0 characters
What is Base64 Encoding?
Base64 is a binary-to-text encoding scheme that converts binary data into an ASCII string format using 64 printable characters. It is commonly used to embed images in HTML/CSS, transmit binary data over text-based protocols like email (MIME) and HTTP, and store complex data in JSON or XML.
The encoding process takes every 3 bytes of input and converts them to 4 Base64 characters, resulting in output that is approximately 33% larger than the original data.
How to Use This Tool
- Choose "Text Mode" to encode/decode plain text, or "File Mode" to encode a file.
- In Text Mode, paste your text and click "Encode →" or "← Decode".
- In File Mode, drag and drop any file or click to upload.
- Copy the Base64 result or download it as a text file.
Base64 Character Set
| Characters | Range | Count |
|---|---|---|
| Uppercase letters | A–Z | 26 |
| Lowercase letters | a–z | 26 |
| Digits | 0–9 | 10 |
| Symbols | + / | 2 |
Frequently Asked Questions
Is Base64 encryption?
No. Base64 is an encoding scheme, not encryption. It does not provide security — anyone can decode a Base64 string. Its purpose is to represent binary data in text-safe format, not to protect information.
Why does Base64 output end with = signs?
The
= characters are padding. Base64 processes input in groups of 3 bytes. If the input length is not a multiple of 3, padding is added to make the output a multiple of 4 characters. One = means 1 byte of padding; two means 2 bytes.How much larger is Base64 than the original?
Base64 encoded output is approximately 33% larger than the original data. Every 3 bytes of input become 4 bytes of output. For example, a 3 KB file becomes roughly 4 KB when Base64 encoded.
Does this tool handle Unicode text?
Yes. This tool properly handles Unicode text (including Chinese, Japanese, emoji, etc.) by first encoding the string to UTF-8 bytes before applying Base64 encoding, ensuring no data is lost during the conversion process.