Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to text, with an optional URL-safe alphabet. Both directions, one tool.
Sponsor
Tool 05 — encode / decode
Idle
Text0 chars
Base640 chars
Local only. Encoding and decoding happen in JavaScript in your browser — nothing is uploaded, even for large payloads.
Examples
hello world→aGVsbG8gd29ybGQ=aGVsbG8gd29ybGQ=→hello worlda?b=c&d→URL-safe: YT9iPWMmZA (no + or /)FAQ
What is Base64 encoding?
Base64 represents binary or text data using 64 printable ASCII characters, so it travels safely through systems designed for text, like email bodies or JSON strings.
How does Base64 encoding work?
Input bytes are grouped into 3-byte chunks and mapped to 4 output characters, with = padding added when the input isn't a multiple of 3 bytes.
What is URL-safe Base64?
It swaps + and / for - and _, so the result can go straight into a URL or filename without extra escaping. Toggle it above.
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