lock WASM / Local Stream • 0 KB Exfiltrated RFC 4648 §4 & §5

Client-Side atob / btoa & TextDecoder • UTF-8 Safe & Binary Stream High Precision Zero-Copy

Universal Base64 Transcoder & Binary Inspector

Encode and decode string literals, binary buffers, or Data URIs directly within your browser’s V8 memory. Full support for unicode code-points beyond ASCII (0x00..0x10FFFF) without truncating multi-byte UTF-8 sequences.

Direction:

Load Presets:

Source Payload UTF-8 String

memory 0 B

0 characters • 1 line

Base64 Output Ratio: 0.00x

analytics 0 B

0 characters • Entropy: 0.00 bits

tune Encoding / Decoding Parameters & RFC Switches

URL-Safe Base64 RFC 4648 §5: Replace + and / with - and _

Pad with '=' Symbol Keep strict 4-character alignment padding

MIME Line Wrap (76 ch) Insert CRLF line breaks per RFC 2045 standard

Theoretical Expansion ~133.33% 4 chars per 3 bytes

Overhead Added +33.3% Safe for ASCII channels

Radix Base Base 64 6 bits per symbol

Process Latency 0.12 ms Sub-millisecond direct

account_tree Bit Stream Inspector 3-Byte Chunk Demo

Live binary chunk walkthrough for characters "Man":

ASCII Chars: M (77) • a (97) • n (110)

3 Octets (24 bits): 01001101 01100001 01101110

4 Sextets (6 bits): 010011 | 010110 | 000101 | 101110

Base64 Indices: 19 • 22 • 5 • 46

Base64 Encoded: "TWFu"

Base64 Alphabet Map A-Z, a-z, 0-9, +, /

A-Z (26) a-z (26) 0-9 (10) Special (2)

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How Base64 Works: Radix 64 Encoding Explained

Base64 is a binary-to-text encoding scheme designed to transport arbitrary binary payloads across media channels that were historically built only to support 7-bit ASCII text (such as SMTP e-mail or early URL query parameters).

3 Bytes to 4 Characters

Every 3 bytes of raw binary data equals 24 bits (3 × 8). The Base64 engine divides these 24 bits into four 6-bit chunks (4 × 6 = 24). Each 6-bit chunk yields an integer index from 0 to 63, mapped directly to an ASCII printable character.

Padding Rules ('=')

When the total input stream is not evenly divisible by 3 bytes, zero bits are padded on the right. If 1 byte remains, two characters and two '==' signs are produced. If 2 bytes remain, three characters and one '=' are appended.

Base64 is NOT Encryption

Base64 does not obfuscate or secure data. Anyone who receives a Base64 string can decode it into its raw origin without any secret key. It is strictly an open serialization format for compatibility, never confidentiality.

RFC 4648 Standard vs URL-Safe Variant

Standard Base64 (RFC 4648 §4) uses + and / as symbols 62 and 63. However, these characters conflict with URL path separators and query parameter percent-encoding. The URL-Safe variant (RFC 4648 §5) substitutes:

+ becomes - (Hyphen-minus)
/ becomes _ (Underscore)
Padding '=' characters are usually omitted in tokens like JWT.

Conversion Reference Table

Standard URL-Safe Use Case

data:image/png;+ data:image/png;- Browser URIs

Auth/Basic: / Auth/Basic: _ OAuth & OpenID

padding: == padding: (none) JWT Bearer