Developer Tools22 May 2026·4 min read
Base64 & URL Encoding Explained for Developers
When to encode, common pitfalls, and how to decode strings safely using free online tools.
Base64 encodes binary data as ASCII text — common in JWT tokens, data URLs, and email attachments. URL encoding (percent-encoding) escapes special characters in query parameters.
Common mistakes
Double-encoding URLs breaks links. Confusing Base64 with encryption is a security risk — Base64 is encoding, not encryption. Always decode on the same charset (UTF-8) you used when encoding.
Try it on NxtTls
Use our Base64 and URL encoder pages for instant encode/decode with copy support. All processing is client-side.
Try the tool
Base64 Encoder