How Client-Side Base64 Encoding & Decoding Works
Base64 Encoder / Decoder (Text, Files, URL-safe) runs entirely in your browser with JavaScript. There is no sign-up, and whatever you type or open here is processed on your device instead of being sent to a server.
Encode and Decode Base64 Data Completely in Your Browser
Convert plaintext to Base64 or decode encoded strings back to readable UTF-8 text directly in browser memory. Unlike cloud conversion utilities that post strings across the network, this tool handles text encoding and decoding 100% on-device. Base64 is an encoding, not encryption: anyone can decode it.
Full UTF-8 Character & URL-Safe Encoding Support
Standard browser atob and btoa functions fail on multi-byte characters like emojis, accents, and non-Latin alphabets. This converter properly handles full UTF-8 byte streams and offers URL-safe Base64 substitution (+ to -, / to _) for web token workflows. The URL-safe option also drops the = padding at the end, and it applies to typed text only; attached files are always encoded as standard Base64.
Direct File Encoding Without Server Uploads
Attach a local image, icon or other file to turn it into Base64 text through the browser's FileReader API; to embed it, put a prefix such as data:image/png;base64, in front. Your original files are never uploaded to any cloud storage.
Why processing in your browser matters
Many online tools upload your files or text to a server to process them. This one does the work on your computer or phone, so your data is not sent to us or stored anywhere else. That lowers the risk when you work with confidential material, although you should still follow your organisation's own rules. Read how this works in our Privacy Policy.
- No uploads: files are opened and saved on your device, so there is no upload or download wait.
- No account: nothing to sign up for or install.
- Free to use: no subscriptions or paywalls.