Encode plain text, binary sequences, and credentials into RFC 4648 Base64 or decode Base64 strings back to clean UTF-8 text.
All formatting, parsing, decoding, and validation executes entirely within your browser using modern Web APIs and JavaScript. Your tokens, JSON payloads, regex inputs, and queries never leave your computer.
Base64 (RFC 4648) is a binary-to-text encoding scheme that translates arbitrary binary data into an ASCII string format using a 64-character set (A-Z, a-z, 0-9, +, and /). It is universally used in HTTP Basic Authentication headers, data URI inline images, email attachments (MIME), and digital certificates.
DevRef's Online Base64 tool handles full UTF-8 Unicode characters without character corruption, supports URL-safe Base64URL encoding (replacing '+' and '/' with '-' and '_'), and provides instant one-click copying. Every operation runs purely client-side in your browser, guaranteeing zero transmission of confidential keys or credentials.
No. Base64 is an encoding scheme, not encryption. It provides zero confidentiality because anyone can instantly decode a Base64 string back to plaintext without a key. Never rely on Base64 alone to protect sensitive data.
Standard JavaScript atob/btoa functions fail on multi-byte UTF-8 characters. DevRef uses modern TextEncoder and TextDecoder Web APIs to safely encode and decode any Unicode character, emoji, or non-Latin script.
Base64 uses '+' and '/', which carry special syntactic meaning in URLs and query strings. Base64URL replaces '+' with '-' and '/' with '_', and typically omits trailing '=' padding to remain completely safe in HTTP URLs.
No. All encoding and decoding runs in local browser memory. No data is sent over the network.
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