Paste a string to validate if it is properly Base64 encoded. Get detailed diagnostics including character set analysis, padding check, and decode test.
A valid Base64 string contains only characters from the Base64 alphabet: A-Z, a-z, 0-9, + and / (or - and _ for URL-safe variant). The string length must be a multiple of 4 when properly padded with = characters.
Common issues include trailing whitespace, line breaks, or characters outside the Base64 alphabet. This validator checks all these conditions and attempts to decode the string to confirm it produces valid binary data.
Common reasons include: spaces or line breaks in the string, characters outside the Base64 alphabet (like @, #, or !), or incorrect padding. The validator will tell you exactly what's wrong.
Technically, proper Base64 requires padding to make the length a multiple of 4. However, many implementations accept unpadded strings. This validator considers unpadded strings as 'valid but missing padding.'
URL-safe Base64 replaces + with - and / with _ to avoid conflicts with URL special characters. This variant is commonly used in JWT tokens, data URIs, and filenames.
Codifica o decodifica cadenas Base64 directamente en tu navegador
Convierte texto a Base64 o decodifica Base64 a texto plano
Convierte imágenes a cadenas codificadas Base64
Decodifica cadenas Base64 a imágenes visibles
Codifica cualquier archivo a una cadena Base64
Decode any Base64 string back to its original file
Decodifica cadenas Base64 a documentos PDF
Decodifica e inspecciona tokens JWT
Codifica o decodifica URLs con codificación porcentual
Convierte caracteres especiales a entidades HTML y viceversa
Convierte entre formatos hexadecimal y Base64
Decode Base64 strings to plain readable text
Decode Base64 and pretty-print as formatted JSON
Generate Base64 data URIs from text or files
Convert Base64 strings to hexadecimal and back
Convert SVG to data URIs for CSS and HTML
Encode text to UTF-8 bytes or decode bytes to text