CloudlessToolsWhat is Base64?
Base64 turns any data, including images and other binary files, into plain letters and numbers so it can be embedded in JSON, HTML, CSS, email or URLs. It is an encoding, not encryption: anyone can decode it, so never use it to hide passwords.
Base64 vs URL-safe Base64
Standard Base64 uses +, / and =, which have special meanings in URLs. URL-safe Base64 (used in JWTs and many APIs) swaps them for - and _ and drops the padding. The decoder here accepts both.
URL encoding
URL component encodes everything except letters, digits and - _ . ! ~ * ' ( ). Use it for query string values. Full URL leaves characters like : / ? & = alone so a complete address stays valid.
Convert an image to Base64
Click File → Base64 to turn any file into a data: URI you can paste straight into HTML or CSS. Paste a data URI into Decode mode to get the file back.