Download
Certificate Doctor is a free MIT-licensed offline Windows utility by ALMARFELD. Inspect X.509 PEM/DER/CER/CRT/KEY/PFX/P12/P7B/P7C; match private keys, check provided chain signatures and flag expiry/weak-key issues. Convert new copies and export HTML/JSON reports without key material or passwords. v1.0.1 refuses unverified issuer signatures and reports locked/unreadable inputs. No OCSP/CRL revocation, AIA fetching, hostname or trust-store checks. A complete supplied chain is not proof of browser trust. No signing or CSR generation. Limit: 8 MiB per file, 32 files. Originals and existing outputs are never overwritten. Windows 10/11 x64 portable ZIP: extract fully and run CertificateDoctor.exe. Separate WebView2 Runtime required, never automatically installed. No uploads, accounts or telemetry. The executable is not Authenticode signed.
Features
- Inspect certificate details and SHA-1/SHA-256 fingerprints
- Open PEM, DER, CER, CRT, KEY, PFX/P12 and P7B/P7C
- Build chains from supplied files with signature verification
- Find expiry, weak-key and signature-algorithm warnings
- Match private keys to certificates
- Export new PEM, DER, P7B or PFX copies and HTML/JSON reports
Project Samples
