Base64 encode/decode · Guide
How to Encode and Decode Base64 Online
Encoding and decoding Base64 is a two-click operation once you know the flow. Here is how to do it reliably, including the Unicode gotcha that trips people up.
Encoding text
Choose encode, paste readable text, and the tool returns a Base64 string. The output is longer than the input — Base64 grows data by about a third — which is expected.
Decoding a string
Choose decode and paste the Base64. Valid input returns the original text. If you see an error or garbled output, the string may be truncated, contain whitespace, or use the Base64url variant.
Unicode done right
Naive Base64 implementations mangle non-ASCII characters. This tool encodes via UTF-8 bytes, so accented letters, CJK text and emoji round-trip correctly.
Frequently asked questions
Can I use this for production work?
Yes, for inspection, formatting and quick generation. Still review the output before committing it to production code or configuration.
Ready to try it?
Open the free browser-based Base64 encode/decode and apply what you just read — no sign-up, runs locally.
Open the Base64 encode/decode tool