無料Base64エンコーダー＆デコーダー

Yes, the Base64エンコーダー on Allio Tools is completely free with no sign-up or registration required. It works directly in your browser.

ブラウザでテキストをBase64にエンコードし、Base64文字列をデコードします。 No data is sent to a server — everything runs locally in your browser for maximum privacy and speed.

No installation needed. The Base64エンコーダー runs entirely in your web browser on any device — desktop, tablet, or mobile.

Completely safe. The Base64エンコーダー processes everything locally in your browser. No input data, results, or usage information is ever transmitted to or stored on any server.

After the page loads for the first time, the Base64エンコーダー works without an internet connection for all client-side processing. Tools that fetch live external data (such as DNS or network lookups) require an active connection.

Yes. The Base64エンコーダー is a utility tool and its output carries no licensing restrictions. You are free to use results in any project, commercial or personal.

Yes. The Base64エンコーダー is built to comply with the relevant industry standard or specification for this utility type. If you encounter an unexpected result, verify your input against the specification — edge cases outside the standard may produce undefined behaviour.

Yes. The Base64エンコーダー is built with standard browser APIs and works on all modern browsers including Chrome, Firefox, Safari, and Edge — on both desktop and mobile. No plugins, extensions, or third-party software are required.

Select and copy the result text to paste into any document or app. For image tools, a Download button saves the file directly to your device. Your browser's built-in screenshot function also captures results quickly. No account or login is required.