FREE TOOLS
X509 Certificate Inspector
Inspect complete X509 certificate names,extensions and original signed bytes.
Certificate, Optional public source file (takes precedence)
JSON
Browser only
Runs locally in your browser. Your files, pasted content and generated output are not uploaded. Reset clears this tool’s working data.
This tool needs JavaScript. If it does not load, refresh the page and try again.
How to use this tool
- Enter the displayed example values,or choose the local input files requested by the controls. Optional source files take precedence where labelled.
- Choose Inspect certificate and inspect the complete result and any reported limitations.
- Use Download result and each companion download link to save complete outputs. Reset clears output and restores example controls.
Examples
Certificate: -----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
Limitations
- Inspect one X509 certificate supplied as PEM,Base64 DER or a real DER file. Download version,serial,grouped issuer/subject attributes,validity declarations,public-key/signature algorithms,signature bytes,all extension OIDs/critical flags/raw payloads,available typed interpretations,unique IDs and exact signed bytes. Unknown extensions remain raw. This is metadata inspection;it does not verify signatures,chains,revocation,hostname,current-time validity or trust. Up to100,000 characters per pasted field,128 KiB per optional file,400,000 combined input bytes and4 MiB output. ASN.1 trees are bounded to20,000 nodes/40 levels. All processing stays in your browser.
- Complete outputs only. Unsupported or oversized input is refused. Follow the displayed job-specific bounds and format policies.