🔐Base64 Encoder / Decoder

How to Use

1. 1

   Choose a mode

   Select Encode to convert text to Base64, or Decode to convert Base64 back to text.

2. 2

   Enter your text

   Type or paste the input in the text area. Japanese and other Unicode characters are fully supported.

3. 3

   View the result

   The encoded or decoded result appears instantly in the output area.

4. 4

   Copy or swap

   Click Copy to save the result to your clipboard. Use Swap to move the output back to input and flip the mode.

FAQ

What is Base64 encoding?

Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). It is commonly used to embed binary data in text-based formats such as emails (MIME), JSON, and data URIs.

What is URL-safe Base64?

URL-safe Base64 (RFC 4648 §5) replaces + with - and / with _ to make the encoded string safe for use in URLs and filenames without percent-encoding. Padding characters (=) are also removed.

Can I encode Japanese or other Unicode text?

Yes. The tool encodes text as UTF-8 bytes before applying Base64, so any Unicode character — including Japanese, Chinese, Arabic, and emoji — is fully supported.

How much does Base64 increase the data size?

Base64 encoding increases the data size by approximately 33%. Every 3 bytes of input become 4 Base64 characters. For example, 1 KB of data becomes about 1.37 KB after encoding.