Base64 Encoder & Decoder
Instantly encode text or files into Base64, or decode strings back to readable text and binary files. Fast, secure, and strictly client-side.
Options
Replaces+ with - and / with _ to ensure the resulting string can be safely used in web URLs.About the Base64 Encoder & Decoder
The Neuctra Tools Base64 utility is designed for developers who frequently need to convert data formats for APIs, CSS embedding, or data transfer. It supports standard text, full files, and maintains perfect compatibility with UTF-8 character sets (including emojis and special symbols).
By processing everything on the client side via the browser's native Web APIs, your data remains completely private. Whether you're decoding a JSON Web Token (JWT) payload, converting an image to a data string, or decoding a binary file backup, nothing is ever uploaded to a remote server.
Common Use Cases
Embedding Images
Convert small images into Base64 strings to embed them directly into HTML or CSS files, reducing HTTP requests and speeding up initial page loads.
API Authentication
Basic HTTP Authentication requires credentials to be formatted as username:password and encoded in Base64 before being sent in the authorization header.
JSON Web Tokens (JWT)
The header and payload sections of a JWT are encoded using URL-safe Base64. You can easily decode these segments to inspect the token's claims.
Data Transfer
XML and JSON do not natively support binary data. Converting files (like PDFs or ZIPs) to Base64 allows them to be safely transported inside standard text-based payloads.