Question 1

What is Base64 used for?

Accepted Answer

Base64 is used whenever binary data needs to be stored or transmitted over a medium that only supports text. Common use cases include embedding images in CSS or HTML via data URIs, encoding email attachments (MIME), storing cryptographic keys and certificates in PEM format, and passing binary payloads in JSON APIs.

Question 2

Is Base64 encryption?

Accepted Answer

No. Base64 is encoding, not encryption. It transforms data into a different representation but provides no security or confidentiality. Anyone can decode a Base64 string without a key. For secure transmission, always use proper encryption (e.g., AES or TLS) in addition to Base64.

Question 3

What is the difference between Base64 and Base64 URL-safe?

Accepted Answer

Standard Base64 uses + and / as characters in its alphabet, which have special meanings in URLs. URL-safe Base64 replaces + with - and / with _, making the output safe for use in URLs, filenames, and HTTP headers without additional percent-encoding.

Question 4

Why does Base64 output end with = signs?

Accepted Answer

Base64 encodes 3 bytes at a time into 4 characters. If the input length is not a multiple of 3, padding characters (=) are added to the output so that its length is always a multiple of 4. One or two equal signs at the end of a Base64 string are completely normal.

Question 5

Does my data stay private?

Accepted Answer

Yes. This tool runs entirely in your browser. Your text or binary data is never sent to any server. You can even use it offline after loading the page once.

Base64 Encoder/Decoder

What is Base64 encoding?

How does it work?

FAQ