Offline Base64

Encode and decode Base64 locally. No permissions, network requests, or saved history.

Convert Base64 without pasting your text into a website. Offline Base64 processes your input directly in Chrome, using only code packaged with the extension. Features: Encode UTF-8 text to Base64 and decode Base64 back to text. Work with Chinese, emoji, and other Unicode text. Decode standard or URL-safe Base64, including unpadded and multiline input. Generate URL-safe Base64 without padding. Reverse the result after decoding, then copy or download it. Convert up to 32,000 characters per box, with a visible size limit. Open local UTF-8 text files within that limit (up to 96 KB). Decode binary Base64 and download the original bytes. Open the converter in a tab when you want a larger workspace. Privacy: No extension permissions or website-access permissions requested. No network requests, analytics, advertising, accounts, or remote scripts. Network connections are blocked by the extension's Content Security Policy. No conversion history or input is saved by the extension. Copying and downloading happen only when you click the corresponding button. The toolbar popup clears its contents when it closes. Use Open in a tab if you want to keep working until you close or reload that tab. Base64 is an encoding format, not encryption. This extension does not encrypt your information or change the behavior of Chrome, your clipboard, or other extensions. Support: zhangtianlin15@gmail.com