~/tools / base64
// dev

Base64 & URL Encoder / Decoder

Choose a codec and a direction. Text is handled as UTF-8, so accents and emoji survive the round trip.

● runs 100% in your browser — nothing is uploaded

Output

Base64 vs Base64URL

Base64 turns every 3 bytes into 4 printable characters from A–Z a–z 0–9 + /, padding with =. Base64URL swaps + and / for - and _ and usually drops the padding, so the result is safe inside URLs, file names and JWTs. Base64 is an encoding, not encryption: anyone can decode it.

Component vs full URL encoding

Component (encodeURIComponent) escapes everything that has meaning in a URL, including / ? & = — use it for a single query-string value. Full URL (encodeURI) leaves the URL structure intact and only escapes spaces and non-ASCII characters.

Common uses

  • HTTP Basic auth headers: Authorization: Basic base64(user:password)
  • Kubernetes Secrets, data URIs, email attachments (MIME)
  • Reading the payload of a JWT or a SAML response