Base64 Converter

Encode and decode text, files and images to Base64. Data URI output, URL-safe, MIME wrapping. All in the browser, no upload.

What it is

Utilverse's Base64 Converter is the most complete tool to encode and decode anything to and from Base64 online. Turn text, binary files and images into Base64 strings — and back — with live two-way conversion, image previews, full Data URI generation, URL-safe variants, MIME line wrapping, multiple charsets and ready-to-paste HTML/CSS/Markdown snippets. Everything runs in your browser: your content never leaves your device.

Encode and decode with one click
Supports text, files, and images
Data URI ready for HTML and CSS

How it works

Pick a mode

Choose Text, File or Image. In text mode the app auto-detects whether you want to encode or decode.

Paste or drop

Paste your text, drop a file in the drop zone or pick an image. The conversion starts instantly.

Copy or download

Copy the result to your clipboard, download it as a file, or grab the ready-made HTML/CSS/Markdown snippets.

Features

Live Encode & Decode

Instant bidirectional conversion with auto-detect: paste Base64 to get the text, paste text to get Base64.

Files & Images

Drag & drop any file up to 25 MB, preview decoded images, output as Data URI with automatic MIME detection.

Professional Options

URL-safe (RFC 4648 §5), optional padding, MIME 64/76 line wrapping, UTF-8, ASCII and ISO-8859-1 charsets.

Privacy First

Everything happens in your browser. No uploads, no sign-up, no tracking of content: your data stays on your device.

FAQ

Are my files uploaded to a server?

No. Encoding and decoding run entirely in your browser via JavaScript: your data never leaves your device.

What's the difference between standard and URL-safe Base64?

URL-safe Base64 replaces "+" and "/" with "-" and "_", so the output is safe to use in URLs, JWTs and file names.

Can I get a Data URI directly?

Yes: enable the "Include Data URI prefix" option or use Image mode — the output will be in the form data:image/png;base64,... ready for <img>, CSS or Markdown.

What's the maximum file size?

To keep things snappy in the browser, the cap is 25 MB per file. For larger payloads we recommend command-line tools like openssl or base64.