Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to readable text. Supports standard and URL-safe Base64. Runs locally in your browser.
Text (Input)
Output
Tip: You can verify in DevTools → Network that nothing is uploaded.
Encoding options
About this Base64 Tool
Base64 Encode / Decode converts text into Base64 (an ASCII-safe representation) and can decode Base64 back into text. Base64 is commonly used in APIs, JSON payloads, config files, and data transfer where binary-safe text is required.
This tool runs entirely in your browser. If decoding fails, it usually means the input is not valid Base64 (invalid characters, missing padding, or corrupted data).
- Encode text to Base64 format
- Decode Base64 back to original text
- URL-safe Base64 variant support
- Proper Unicode/UTF-8 handling
- Enable Auto to convert as you type
- Use URL-safe variant for URLs and filenames
- Upload text files to encode/decode
- Invalid Base64 will show an error message
FAQ
No. Everything runs locally in your browser. Nothing you paste is sent to a server.
After the page loads once, it will typically keep working offline (unless you hard refresh with no cache).
No. Your input stays in your browser. Only optional preferences like theme or language may be stored.
Any plain text. You can paste text directly into the input box.
Base64 represents data using only ASCII characters, making it safe to embed in text formats like JSON, XML, and URLs (with the URL-safe variant).
Decoding can fail if the input contains invalid characters, incorrect padding (=), or has been truncated. Remove whitespace and verify the string is valid Base64.
URL-safe Base64 replaces + with - and / with _ and often omits padding = so the result can be used safely in URLs and filenames.