About this tool
Base64 shows up constantly in development: embedding images in CSS, crafting Authorization headers, encoding blobs for JSON payloads, or debugging tokens. This encoder and decoder handles both text and files, entirely on your machine. Type or paste text and get instant Base64 with proper UTF-8 handling — accented characters, CJK text and emoji encode correctly, unlike naive btoa-based tools that choke on anything outside Latin-1. Flip the URL-safe switch to get the RFC 4648 alphabet with dashes and underscores instead of plus and slash, exactly what you need for JWTs and URL parameters. Decoding validates the input and reports exactly where invalid input breaks instead of failing silently. For files, drop any file and receive its Base64 data — useful for small assets you want inline — or paste Base64 to download the decoded file. Nothing is uploaded: the conversion uses local browser APIs, so credentials and internal data stay private. It is a small tool that removes a daily friction point for developers.
How to use Base64 Encoder & Decoder
- Type or paste text into the input, or drop a file onto the page.
- Choose Encode or Decode, and toggle URL-safe mode if needed.
- The result appears instantly with correct UTF-8 handling.
- Copy the output or download the decoded file.
Frequently asked questions
Does it handle non-ASCII text?
Yes. Full UTF-8 support means Chinese, Arabic, emoji and accented characters encode and decode correctly.
What is URL-safe Base64?
A variant that replaces + and / with - and _ so the result can sit safely inside URLs and filenames — used by JWTs, for example.
Is there a file size limit?
No hard limit, though very large files make huge Base64 strings; a few hundred megabytes works fine on a modern machine.
Is my data uploaded?
No. Encoding and decoding run locally in your browser; nothing ever leaves your device.