SSL Checker Tool — Free SSL Certificate Checker & Online Analysis
for Developers, DevOps & Admins
Diagnose, convert, and secure your infrastructure with our suite of modern SSL tools. Fast, private, and always free.
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Professional SSL & Certificate Management Tools
SSL Checker
Diagnose SSL certificate installation issues, verify trust chains, and check expiration dates instantly.
SSL Converter
Seamlessly convert between PEM, PFX, DER, and P7B formats for any server type.
CSR Generator (RSA & ECC)
Generate secure 2048/4096-bit RSA or modern ECC (Elliptic Curve) CSRs and Private Keys.
TLS Scanner
Deep security scan for weak protocols (SSLv3, TLS 1.0) and known vulnerabilities.
Cert Decoder
Decode X.509 certificate files to view subject, issuer, SANs, and other details.
Bulk SSL Checker
Monitor the SSL health of up to 100 domains at once with a single click.
More Essential Utilities
Key Matcher
Match your private key with your certificate to ensure they go together.
CSR Decoder
Decode and verify the contents of your Certificate Signing Requests.
DNS & Bulk DNS
Research DNS records for any domain or process hundreds in bulk instantly.
Certificate Search
Search CT logs to discover all certificates issued for a domain and subdomains.
Redirect Checker
Trace the full path of any URL redirect and analyze server response headers.
Vulnerability Checker
Perform a security audit of your website. Check headers, sensitive files, and SSL flaws.
Why Engineers Trust SSL Tools
Built for reliability, privacy, and speed.
Ultra Fast Analysis
Our optimized backend delivers analysis results in under 2 seconds average.
Zero-Knowledge Privacy
We never store your keys or certificates. Data is processed in volatile memory only.
Developer First
Clean APIs (coming soon) and mobile-responsive value for on-call debugging.
Professional SSL Certificate Management
What is an SSL Checker?
An SSL checker is a diagnostic tool that verifies your website's SSL/TLS certificate is correctly installed and trusted. It checks the certificate expiration date, identifies the issuing Certificate Authority (CA), and validates the entire certificate chain to ensure users won't see "Not Secure" warnings in their browsers.
The Importance of TLS Security Scanning
Beyond simple validity, our TLS Scanner evaluates your server's protocol support. We help you identify weak legacy protocols like SSLv3 or TLS 1.0/1.1 that should be disabled to maintain PCI compliance and protect user data from modern vulnerabilities.
Why Use Our Free SSL Tools?
We provide a developer-first experience with zero-knowledge privacy. Whether you need to convert PEM to PFX, generate a 2048-bit CSR Certificate Signing Request, or decode an X.509 certificate, our tools process everything securely in your browser or through volatile memory, never storing your private keys.
Frequently Asked Questions
How do I check my SSL certificate?
Use our free SSL Checker tool by entering your domain name. The tool will verify your certificate's validity, expiration date, certificate chain, and proper installation in seconds.
How do I convert PEM to PFX?
Use our SSL Converter tool. Select 'PEM' as the source format and 'PFX' as the target format. Upload your certificate and private key, optionally add a password, and click convert.
What is a Certificate Signing Request (CSR)?
A CSR is a block of encoded text that contains information about your organization and domain. You submit it to a Certificate Authority like DigiCert or Let's Encrypt to obtain an SSL certificate.
Are these SSL tools safe to use?
Yes! We follow a zero-knowledge security model. All processing happens in volatile memory or locally in your browser (where applicable), and we never store your private keys or certificates. We value your privacy and security above all else.
Secure Your Infrastructure Today
Join thousands of DevOps professionals using SSL Tools to monitor and maintain their security certificates.
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