Free · No signup

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 back to text — UTF-8 safe, with an optional URL-safe variant for tokens and query strings.

Processed in memory — never stored, no account needed.

What Base64 is (and isn't)

Base64 represents binary data using 64 printable characters (A–Z, a–z, 0–9, + and /), so it can travel safely through channels designed for text: JSON payloads, HTTP headers, email bodies, data URIs. Three bytes of input become four characters of output — about 33% overhead.

Base64 is not encryption and offers zero confidentiality: it is trivially reversible, which is exactly what this tool does. If you need secrecy, encrypt; if you just need binary-to-text transport, Base64 is the right tool.

The URL-safe variant (base64url, RFC 4648 §5) replaces + with -, / with _ and drops the padding = signs, so encoded values survive inside URLs and file names untouched. JWTs use base64url for all three of their segments.

Testing APIs that speak Base64?

ContinuumNexus monitors your endpoints with custom headers and body assertions — including Base64-encoded credentials.

Start monitoring free Explore features

Frequently asked questions

Is Base64 secure for passwords or secrets?
No. Base64 is an encoding, not encryption — anyone can decode it instantly. HTTP Basic authentication uses Base64 only for transport formatting, which is why it must always run over HTTPS.
Why does my Base64 string end with = signs?
Base64 works in blocks of 3 input bytes → 4 output characters. When the input length isn't a multiple of 3, the output is padded with one or two = characters. The URL-safe variant usually omits them.
What is the difference between Base64 and base64url?
base64url replaces the two characters that clash with URL syntax: + becomes - and / becomes _, and padding is typically dropped. Use it for anything embedded in URLs, cookies or file names — JWTs are the most common example.
Does this tool handle emoji and accented characters?
Yes — text is converted to UTF-8 bytes before encoding and decoded back from UTF-8, so accents, emoji and any Unicode text round-trip correctly.