When should I use the URL-safe alphabet?

Whenever the result goes in a URL, a filename or a JWT. Standard Base64 uses + and /, both of which have meaning in a URL and will be mangled or misread.

Why does my encoded string end in equals signs?

Padding. Base64 works in groups of three bytes; when the input does not divide evenly, = characters fill the gap. The URL-safe variant usually omits them.

Base64 Encoder

Encode UTF-8 text to Base64, standard or URL-safe.

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About this tool

Text is encoded as UTF-8 bytes first, so non-ASCII characters survive the trip. URL-safe mode swaps + and / for - and _ and drops the padding.

Limitations

Base64 is an encoding, not a cipher. Anyone can reverse it.

Questions

When should I use the URL-safe alphabet?: Whenever the result goes in a URL, a filename or a JWT. Standard Base64 uses + and /, both of which have meaning in a URL and will be mangled or misread.
Why does my encoded string end in equals signs?: Padding. Base64 works in groups of three bytes; when the input does not divide evenly, = characters fill the gap. The URL-safe variant usually omits them.

Privacy

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