URL Encoder/Decoder

Base64 encoding converts binary data into a text string using a specific 64 character set.

• A-Z (26 characters)
• a-z (26 characters)
• 0-9 (10 characters)
• + and / (2 characters)

In addition to the 64 characters, the = character is used at the end to make the Base64 string a multiple of 4. This is necessary for accurate decoding.

For example, when the string convertchief.com is encoded in Base64, it becomes Y29udmVydGNoaWVmLmNvbQ==.

Base64 is used for

• embedding images in CSS/HTML (data URLs)
• encoding email attachments
• storing binary data in JSON/XML
• transmitting binary files over text-only channels
• and so on

A Base64 string must have a length that is a multiple of 4 characters (each group of 3 bytes, or 24 bits, is encoded as 4 Base64 characters).

If a Base64 string's length is not a multiple of 4, = characters are added at the end for padding.

No, not all text strings can be decoded using Base64. It's because a valid Base64 encoded data can't contain characters other than A–Z, a–z, 0–9, +, /, and possibly = for padding.

If you try to decode a string that contains characters other than the above, our Base64 decoder tool will show you an error message.

URL-safe Base64 format is a variant of Base64 encoding that replaces + with - and / with _ so that it can be safely used in URLs and filenames.