Base64 Certificate Decoder
Got a base64 blob and not sure what is inside? Paste it. We auto-detect PEM, bare base64, or hex; report what each block looks like (X.509 cert, CSR, generic ASN.1); show the DER bytes; and emit a clean PEM.
Input
Result
Paste, drop, or pick a file.
All decoding runs locally.
What this tool does
Many tools spit out raw base64 with no header. This tool figures out what is inside the bytes (X.509 cert? CSR? something else?), normalises to DER, and re-armours into PEM with the right label. If you have a chain of multiple PEM blocks, all of them are reported.
Reach
PEM, bare base64 (PKCS#7-style), and hex are all accepted.