> Six browser tools: decode a certificate or CSR, check a chain, match a hostname, plan certificate lifetimes and find your error message. Source: https://pkizerotohero.com/tools/ Browser tools # Certificate tools Six small tools for the moments when a certificate gets in your way. They run in your browser, and you need no account. Tool ### [Paste your error](https://pkizerotohero.com/tools/error-finder/) Paste a certificate error from any tool and get the page that explains it. Tool ### [Certificate decoder](https://pkizerotohero.com/tools/decoder/) Paste a PEM certificate and read every field in plain words. Tool ### [Chain checker](https://pkizerotohero.com/tools/chain/) Paste a chain and see which link is missing, expired or out of order. Tool ### [CSR decoder](https://pkizerotohero.com/tools/csr/) Check a certificate signing request before you send it to a CA. Tool ### [Hostname matcher](https://pkizerotohero.com/tools/hostname/) Test whether a name matches a certificate's SANs and wildcards. Tool ### [Lifetime calendar](https://pkizerotohero.com/tools/lifetime/) See how long a certificate may live on any date, and when to renew.