Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 strings — instantly, in your browser.
+ with -, / with _, and omits = padding. Used in JWT tokens and URLs where standard Base64 characters cause issues.
Text → Base64
Base64 → Text
What Is Base64?
Base64 is a binary-to-text encoding scheme that converts binary data into a string of
64 printable ASCII characters (A–Z, a–z, 0–9, +, /).
It is not encryption — it is purely an encoding format used to safely transmit binary data over
text-based channels that may not handle raw bytes correctly.
Base64 Encoding Online — Common Use Cases
JWT tokens use Base64url (URL-safe variant) to encode their header and payload sections. When you decode a JWT with this Base64 decoder online, you can read the claims directly.
Data URIs embed images or files directly in HTML or CSS using
data:image/png;base64,..., eliminating an extra HTTP request.
A Base64 encoding online tool makes it easy to generate these URIs.
APIs and configuration files often Base64-encode binary payloads (certificates, icons, small files) so they can be stored as plain text in JSON or YAML.
Standard vs URL-safe Base64url
Standard Base64 converter output may contain +, /, and =
characters, which have special meaning in URLs and query strings.
Base64url replaces + → - and / → _,
and omits the = padding — making it safe for use in URLs, filenames, and JWT tokens
without percent-encoding.
Unicode and Emoji Support
This base64 encode online tool uses the TextEncoder API to first convert
your string to UTF-8 bytes before encoding. This ensures that multi-byte characters —
such as accented letters (é, ü, ñ), CJK characters (中文), and emoji (🚀) — are handled correctly,
matching how browsers and servers process text.