Base64 Text Encoder & Decoder
Encode plain text to Base64 and decode Base64 strings with full UTF-8 and emoji support, URL-safe mode, and byte telemetry.
About this tool
How to use it
- Select either 'Encode' to convert text to Base64 or 'Decode' to parse a Base64 string back into readable text.
- Paste your text or payload into the input box.
- Optionally enable URL-safe encoding (replaces '+' with '-' and '/' with '_') or automatic 76-character MIME line wrapping.
- Click Encode / Decode or Copy Output to transfer the sanitized string to your clipboard.
Why it matters
Base64 encoding translates binary byte streams and extended UTF-8 text into an ASCII subset of 64 printable characters. This guarantees that emails (MIME), HTTP URLs, and JSON payloads can transmit complex data, cryptographic keys, and emojis without transmission corruption from intermediary mail gateways or proxies.
When to use it
Use this tool when debugging JWT authentication tokens, embedding inline SVG and data URIs in CSS, creating HTTP Basic Auth headers, or transmitting binary payloads over JSON APIs.
Good to know
Standard Base64 encoding expands raw data payload size by approximately 33% (every 3 bytes of input produce 4 ASCII characters). The encoder uses native TextEncoder/TextDecoder APIs, guaranteeing full fidelity for multibyte characters and emojis.
Common questions
What is URL-Safe Base64?
Standard Base64 uses the '+' and '/' characters, which carry reserved meanings in HTTP URLs and filenames. URL-safe Base64 substitutes '+' with '-' and '/' with '_', and frequently omits trailing '=' padding to prevent URI encoding conflicts.
Why does Base64 make data 33% larger?
Base64 encodes 6 bits of data per ASCII character. Because each computer byte contains 8 bits, 3 input bytes (24 bits) require 4 Base64 characters (24 bits), resulting in an exact 4:3 (33.3%) data size expansion ratio.
Does this tool support emojis and foreign languages?
Yes. While legacy JavaScript `btoa()` crashes on characters beyond ASCII Latin-1, this tool uses standard UTF-8 stream processing, ensuring flawless encoding of emojis (🚀), CJK characters, Arabic, and accented scripts.
Is Base64 considered encryption?
No. Base64 is an open encoding scheme designed for data transport, not security. Anyone can decode a Base64 string instantly without a key. Never rely on Base64 alone to protect sensitive passwords or private secrets.