How to create a ERC721 token in OpenSea for Udacity’s Capstone

Alvaro Andres Pinzon Cortes
2 min readMay 4, 2021

Read OpenSea’s docs

The best thing that you can do to learn how to do this is to go over the entire ERC721 Tutorial in OpenSea:

In here I want to highlight some relevant points and ideas from the tutorial.

1. Structuring your smart contract

It is very very very important that you adhere to the latest Open Zeppelin implementation of ERC721. If you do not adhere to it then it is likely that you can have problems.

2. Create your storefront

When you deployed your contract to rinkeby and minted some token you need to click this link to create a storefront and have the tokens in OpenSea

3. Viewing your items on OpenSea

You need to use this URL to access the tokens in OpenSea:

Creating the ERC721Metadata for the Capstone

Solution 1: Complete the ERC721Metadata by coding it yourself

In this github gist you can find a file with a complete ERC721Metadata and the only thing that is to do is the CustomERC721Token contract that inherits from the ERC721Metadata contract.

I want to highlight that people usually make a mistake related to the name, symbol and tokenURI when coding this on their own. Make sure that they are like this:

Solution 2: Use openzeppelin’s contracts and inherit them.

You can use the Ownable, Pausable, ERC721 from openzeppelin instead of having to code them from scratch on your own. In these are the links:

--

--