Base64 Decoder & Encoder Online — Free Converter
Free online Base64 encoder and decoder. Encode text or binary to Base64, or decode Base64 back to its original form — entirely in your browser.
Paste UTF-8 text below and switch between Encode and Decode. Useful for embedding tokens, images and credentials in URLs, JSON or email headers.
Common use cases
- 1Embed credentials, tokens or small images directly into URLs, JSON or email headers safely.
- 2Decode Authorization headers (Basic auth, JWTs) to inspect what your client is sending.
- 3Convert binary attachments to text for systems that only accept ASCII.
Frequently asked questions
Is my input sent to your server?+
No. Base64 encoding and decoding both run in your browser via the standard btoa/atob APIs. Nothing leaves the page.
Why is my decoded output garbled?+
Either the input is not valid Base64 (check for missing padding or stray characters), or the original data was binary, not text. A binary viewer is the right tool for non-text payloads.
Does it handle UTF-8 / emoji?+
Yes. We pipe the input through encodeURIComponent / unescape before btoa so emoji and non-ASCII characters round-trip correctly.