What Base64 Encoding Is and What It Is Not
A plain-English explanation of Base64 encoding, common uses, size overhead and why Base64 should not be confused with encryption.
In this guide
Base64 is encoding
Base64 turns binary data into a text representation using a limited character set. It is useful when a system expects text but you need to represent bytes or other binary information.
It is not encryption
Anyone who has the Base64 text can decode it. There is no secret key involved in ordinary Base64 encoding, so it should never be used as a substitute for encryption or as a way of protecting a password.
Why developers use it
Base64 is commonly encountered in APIs, email-related formats, data URLs and systems that need to carry binary information through text-oriented channels. It is a transport-friendly representation, not a security feature.
Expect some size increase
Base64 usually makes data larger rather than smaller. That trade-off can be acceptable when compatibility with a text-based system matters, but it is worth remembering when sending large files or payloads.
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