Base64 Encoder / Decoder

Encode and decode Base64 strings online. Supports text and hex input with URL-safe Base64 option for Ethereum development.

Input format:

URL-safe Base64 (use - and _ instead of + and /, no padding)

Text Input

Base64 Output

Base64 encodes binary data into ASCII text using 64 characters (A-Z, a-z, 0-9, +, /)
URL-safe variant replaces + with - and / with _ (RFC 4648)
Common uses: encoding ABI data, JWT tokens, data URIs, API payloads
Encoded output is ~33% larger than the original binary data

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