Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to text. UTF-8 safe and 100% in your browser, so nothing is uploaded.
About the Base64 Encode / Decode
The Base64 Encode / Decode tool converts text to Base64 and Base64 back to readable text. Pick a mode, paste your text, and the result appears in the output area. It is UTF-8 safe, so accented characters, emoji, and other non-ASCII text encode and decode correctly. Everything runs in your browser using TextEncoder and TextDecoder, so your text is never uploaded or logged.
How it works
- Choose Encode to turn text into Base64, or Decode to turn Base64 back into text.
- Type or paste your content into the input area on the left.
- Read the result in the output area on the right; in decode mode, invalid Base64 shows an inline error.
- Click Copy to grab the output, or Clear to reset both areas.
Features
- Encode and decode in one place with a mode toggle.
- UTF-8 safe handling using TextEncoder and TextDecoder, so emoji and accented characters survive a round trip.
- Inline error message when a decode input is not valid Base64.
- Character count for the result and one-click copy.
- Runs fully in the browser with no network requests and no external libraries.
Frequently asked questions
Is my text uploaded anywhere?
No. Encoding and decoding happen in your browser with the native TextEncoder and TextDecoder APIs. Nothing is sent to a server or stored.
Does it handle emoji and non-English characters?
Yes. The tool encodes text to UTF-8 bytes before converting to Base64, and decodes back through UTF-8. Characters like é, ñ, 中文, and emoji round trip correctly, which raw btoa cannot do on its own.
Why do I get an invalid Base64 error when decoding?
The decoder accepts only the Base64 alphabet (A to Z, a to z, 0 to 9, plus, slash) with optional padding. Common causes are missing characters, wrong padding length, or pasting text that was never Base64. Spaces and line breaks are ignored.
What is Base64 used for?
Base64 represents binary or text data using printable ASCII characters. It is common in data URIs, email attachments (MIME), JWT segments, and config values that must travel through text-only channels.
Does Base64 keep my data secret?
No. Base64 is an encoding, not encryption. Anyone can decode it back to the original. Use it for transport and formatting, not for protecting sensitive information.