Base64 encode and decode
Handles Japanese and other non-Latin text correctly (many quick converters mangle it), and turns any file into a data: URI — a long text string that can stand in for the file inside a web page.
- Runs entirely in your browser
- Works offline
- No upload
- No sign-up
- No watermark
Loading the tool…
How it works
- Paste text and press Encode or Decode.
- Or drop a file to get its data: URI.
- Copy the result.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see fetch the tool’s own code — and, for a few heavy tools, their open-source engine from a public CDN — plus one small page-view ping to loreatec.jp (page address and title, nothing more). None of them carry your file.
Frequently asked questions
Is Base64 encryption?
No. It only rewrites data using 64 safe characters, and anyone can turn it back instantly — treating it as a secret is a common cause of security incidents. It also makes the data about a third bigger.
Does anything leave my browser?
No. Nothing is sent to a server. The whole tool is a small program that runs inside your browser tab. Once the page has loaded, it keeps working even with the internet switched off.