Base64 Encoder / Decoder
Encode text to Base64 and decode it back, in your browser.
What this tool does
Base64 Encoder / Decoder converts text to Base64 and back as you type, entirely in your browser. It is UTF-8 aware, so accented letters, Korean, Japanese, and emoji survive a round trip, and it can produce the URL-safe alphabet used in tokens and query strings.
How to use
- Choose Encode or Decode.
- Type or paste your text — the result updates instantly.
- For tokens and URLs, tick the URL-safe alphabet option.
- Click Copy to grab the result.
Notes
- Everything runs locally — your text is never uploaded.
- Base64 is encoding, not encryption: anyone can decode it.
- Decoding accepts both alphabets and tolerates missing padding.
Frequently asked questions
Is Base64 a form of encryption?
No. Base64 only changes how bytes are written so they survive text-only channels such as email or JSON. Anyone can decode it instantly, so never use it to protect secrets.
What does the URL-safe option change?
It swaps the + and / characters for - and _ and drops the trailing = padding, so the result can sit in a URL or filename without being escaped. Decoding here accepts either alphabet automatically.
Why did my decode fail?
Either the input is not valid Base64, or it decodes to raw binary rather than text. This tool decodes to UTF-8 text, so Base64 of an image or a zip file will report an error instead of showing garbled characters.
Does it handle emoji and non-English text?
Yes. Text is converted to UTF-8 bytes before encoding, so any Unicode content round-trips exactly — unlike the browser's raw btoa(), which fails on non-Latin-1 characters.