How to recognize valid Base64 text
Base64 normally contains letters, numbers, plus and slash characters, with optional equals-sign padding. Base64URL uses hyphens and underscores. This tool ignores whitespace and accepts both common variants.
Common decoding problems
- Missing or extra characters cause invalid input, so check that the copied value is complete.
- The Base64URL characters - and _ are handled as their standard Base64 equivalents.
- Garbled output usually means the original bytes were not UTF-8 text or used a different character encoding.
Security and privacy
Decoding does not prove that content is safe. Base64 is only a representation and may contain scripts, documents, or binary files. Do not put sensitive Base64 in a URL; this tool processes input in the current browser session and does not retain results.
Base64 is not encryption
Anyone can decode Base64 data, so it cannot replace encryption, signing, or access control. Protect confidential data with a proven encryption design and careful key management.