How to determine secp256r1 or secp256k1 is used on the web sites I'm pretty new at Cryptography (and at Cryptanalysis), but I went to the website Elliptic to try to discover the elliptic curve they use, and I found they use ECDP 256. So, by SEC2 I discovered they do use either secp256r1 or secp256k1. How can I know which one they do use? I do also need to find the base point they are using. Where can I find that? Thanks.
If you look at the all information on the site that provides you can find the answer very fast.

X9.62 ECDSA Signature with SHA-256

X9.62 : Public Key Cryptography for the Financial Services Industry: The Elliptic Curve Digital Signature Standard (ECDSA)&quot;
So, it is the NIST curve and NIST uses the $r$ versions like secp256r1.

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