Most online Base64 tools send your input to a server. That's a problem when
you're decoding JWT tokens, API keys, or auth headers.
decode64.com runs entirely in your browser using native JavaScript — nothing
is ever uploaded. Paste your Base64 string and get the result instantly.
→ Decode Base64 to text
→ Encode text or any file to Base64
→ Supports Base64URL (JWT tokens with - and _)
→ Drag & drop file support
→ Copy to clipboard, swap input/output
