Encode and decode Base64 online
Base64 is a binary-to-text encoding that represents any data using 64 safe ASCII characters, so it can travel through channels built for plain text — email bodies, JSON payloads, HTML data URIs, and HTTP headers. This free Base64 converter encodes text to Base64 and decodes Base64 back to readable text in one place, with a live output box and a one-click Copy Output button.
How to use the Base64 encoder and decoder
- Paste your text or an existing Base64 string into the Input box.
- Click Encode to Base64 to convert plain text into a Base64 string.
- Or click Decode from Base64 to turn a Base64 string back into readable text.
- Use Copy Output to grab the result. If the input is not valid Base64, the tool shows an error instead of a broken result.
Common uses for a Base64 converter
- Reading or building
data:URIs for inline images, fonts, and other embedded assets. - Inspecting Base64 values found in config files, API responses, and environment variables.
- Encoding small blobs so they survive systems that only accept text.
- Decoding Basic Authentication headers and other Base64-wrapped credentials while debugging.
Everything runs in your browser
All encoding and decoding happens locally in your browser using native JavaScript — your text is never uploaded, logged, or stored on our servers. That makes it safe for sensitive strings you would rather not paste into a random online service. Note that Base64 is encoding, not encryption: anyone can decode it, so it is not a way to protect secrets.
Working with the parts of a token or URL-encoded data? A JSON Web Token is just Base64url segments — inspect one with our JWT decoder — and for percent-encoded query strings use the URL encoder and decoder.
Need a custom tool or internal developer utility built for your team? Get in touch with SR Infobiz.