What it does
Useful, focused capabilities
- UTF-8 text and binary files
- Base64 and Base64URL
- Optional padding, line wrapping, and Data URLs
- Strict decode validation
- Binary result download
Developer utilities · browser-local
Base64 encoder and decoder
Encode text or files to Base64 and decode Base64 or Base64URL locally, with strict validation, Data URL output, and binary download.
Work happens in the current browser. The route does not require an account or a server-side processing job.
Interactive browser workspace
Base64 encoder and decoder
The live tool is loaded in this browser only. This route does not need camera, microphone, or screen-capture permission for its main task.
Open this local tool →Browser compatibility
Requirements and honest fallbacks
JavaScript and the File API for optional local file input and download.
- JavaScript
- TextEncoder and TextDecoder
- File API
- download support
Questions people ask
Clear answers and limits
Is Base64 secure?
No. Anyone can decode it. Use encryption when confidentiality is required.
Why is the encoded output larger?
Base64 represents each three source bytes with four characters, usually adding about one third before headers or line breaks.
What is Base64URL?
It replaces + and / with URL-friendlier - and _. Padding may also be omitted depending on the consuming format.
Can binary output be previewed as text?
Only when the decoded bytes form valid UTF-8. Otherwise the page suppresses a misleading text preview and offers a file download.
Are Data URLs uploaded?
No. A Data URL is just a text representation created locally, but pasting it into another service can disclose its contents there.