使用方法
- Paste a PEM-encoded certificate or key block into the input field (beginning with -----BEGIN ...)。
- The tool validates the PEM structure and reports the block type, number of base64 lines, and DER byte size。
- Read the success or error alert to confirm whether the PEM format is valid。
- For full X.509 field decoding (issuer, SAN, validity dates), use the OpenSSL command shown in the hint。
範例
- Pasting a valid -----BEGIN CERTIFICATE----- block shows type CERTIFICATE, the base64 line count, and the DER size in bytes。
- Pasting a block with a missing or mismatched footer line triggers an error alert describing the structural problem。