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CSR Decoder

Check your CSR before ordering an SSL certificate: see at a glance whether the domains, company details, key type and size are right.

Guide

What is a CSR?

A CSR (Certificate Signing Request) is the text you send to the certificate authority when you apply for an SSL certificate. It contains the domain the certificate is for, your company details and the public key generated on your server.

A CSR is created together with a private key on your server. The private key stays there and is never shared; only the CSR goes to the certificate authority.

Our CSR decoder reads the CSR you paste, shows what's inside and verifies its signature, so you don't end up with a certificate for the wrong domain or company name. Your CSR isn't stored.

What the Fields Mean

Common name (CN): The certificate's main domain, e.g. www.example.com. For a wildcard, use *.example.com.
Organization (O) and unit (OU): Your legal company name, verified for OV and EV certificates. Not used for DV.
City, state and country: Where the company is based. The country is a two-letter code, e.g. TR or GB.
Domain names (SAN): Additional names the certificate will cover. Modern clients read domains from this field.
Key: Use at least 2048-bit RSA, or ECDSA with P-256 or P-384.
Signature: "Valid" means the CSR was signed with the key inside it and hasn't been altered since.

Frequently Asked Questions

How do I create a CSR?

In cPanel and Plesk it takes a few clicks in the SSL/TLS section. On the command line: openssl req -new -newkey rsa:2048 -nodes -keyout example.key -out example.csr. Keep the resulting .key file somewhere safe.

Is it safe to paste my CSR here?

Yes. A CSR contains only the public key and is meant to be sent to a certificate authority anyway. It isn't stored after decoding. Never paste your private key into any website; if the tool spots one, it warns you without sending it.

I made a mistake in my CSR. What now?

A CSR can't be edited. Generate a new CSR and private key with the correct details and use the new one for your order.

Do I need separate CSRs for www and non-www?

No. Most certificate authorities add example.com for free when you apply for www.example.com. For other domains, add them to the SAN field or choose a multi-domain certificate.

Should I choose RSA or ECDSA?

2048-bit RSA is supported everywhere. ECDSA gives the same security with a shorter key and is faster; it's a good choice unless you need to support very old devices.

CSR Ready? So Is Your Certificate

Get DV, OV, EV or Wildcard SSL from ADVEYER, then confirm the installation with our SSL checker.

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