Base64 Online Encoder & Decoder
Encode text or decode Base64 strings instantly. Don't worry, everything runs in your browser and no data will ever sent to our server.
100% private
No data leaves your browser.
Instant results
Output updates as you type.
Unicode support
Handles UTF-8 characters correctly.
Frequently Asked Questions
Base64 is a way to represent binary data as a string of printable ASCII characters. It converts every 3 bytes of input into 4 characters chosen from 64 printable characters (A-Z, a-z, 0-9, + and /). The output is about 33% larger than the input but safe to pass through any text-based system.
Use it when you need to pass binary data through a system that only handles text. Common cases: embedding images in HTML or CSS via data: URIs, sending file data inside JSON payloads, encoding binary blobs for text field storage, and attaching files in email MIME messages.
This browser tool works best with text input. Encoding raw binary files like images or PDFs requires reading raw bytes directly. For that use case, look for a dedicated file-to-Base64 converter that accepts file uploads.
Yes. Regular Base64 uses + and / which are reserved characters in URLs. URL-safe Base64 replaces + with - and / with _, making the output safe for URLs and filenames without any percent-encoding. Both variants encode the same data, just with a slightly different character map.
No. Everything runs directly in your browser. Your input never leaves your device. There is no server component to this tool and nothing you enter is ever logged or stored anywhere.