Nostr is a social network protocol that unites the bitcoin community and binds them with the lightning network zaps. So the social network also has the verification marks like twitter and other socials. So if you want them you can either pay to the social network that are premium plans or you can get it using the free option too. 

Take example of Primal.net where you can use the lightning address and the NIP-50 address domain which can give you the username verification mark.

For this I am using nostr verification site.  

Next step is giving your details of the username on nostr and the hex value. Here the hexvalue can be created using the npub and nsec. Use the below tool to convert the npub and nsec into the hex value. 

Now use the hex key in your verification details. 

Now the thing is that you are going to add the details when the NIP50 domain data is returned to you as a reply. Use that in your respective profile field for the NIP50 text field. 

Once this is added in 1 hour or more you would find the checkmark appearing in the Nostr based websites like primal.net, iris.to and other types ofthe websites etc. And you would have the details of the checkmark like below post. You can get colored checkmarks and also custom domains if you payfor the monthly service. 

I hope this tutorial helps with the checkmark in Nostr. 

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