【How to buy NFT on OpenSea】A Simple Guide on How to Find and Purchase NFT Works!

OpenSea is the world’s leading NFT marketplace; many NFT pieces exist on OpenSea and can be purchased using Ethereum and the Polygon Network as well. However, NFTs are not as easy to purchase for the first time as e-commerce sites, and there are several steps to the purchase process.

This is a point of particular concern for those new to NFT and crypto assets, so we will explain how to find and purchase NFT pieces on OpenSea.

How to search for NFT works at OpenSea

First, we will explain how to find a work on OpenSea.

  1. How to distinguish between ethereal and polygonal works
  2. Search by ranking
  3. Search by entering keywords such as the title of the work in the search window
  4. Use the sorting and narrowing functions.

How to tell the differences between Ethereum and Polygon networks

There are two types of OpenSea works: those using the Ethereum network and those using the Polygon network.

NetworkEthereumPolygon
Number of piecesMoreLess
Volume of transactionsHighLow
Price rangeHighSmall
Gas feerequiredNot required
First sale Gas feerequiredFree of Charge
Auction salesYesNo
Processing speedSlowFast
JPY ExchangePossibleNot Possible

As shown in the table above, it is necessary to distinguish between Ethereum and Polygon pieces, as each has different advantages and disadvantages.

For example, Polygon pieces have fewer pieces than Ethereum, but many of them can be purchased for small amounts and can be listed for free of gas.

Polygon pieces can be identified by the purple hexagon (the Polygon logo) in the lower left corner of each NFT item.

When browsing NFT items, look under the [Chains] section in the left panel under [Polygon].

You can search by chain as follows

Search by Ranking

OpenSea also has the ability to browse top-selling titles.

Quotes from OpenSea

Now you will see the ranking of the most popular works and purchase them from here.

Search by entering keywords such as the title of the work in the search window.

Use the search window to find them.

Use the narrowing and sorting functions

You can also search with narrowing down and sorting.

If you want to search by genre, click on the arrows below to search by various genres.

Process of Purchasing Ethereum Works

Here is how to purchase Ethereum pieces.

You can purchase ethereum pieces by following the steps below.

  • 1.  Transfer Ethereum to MetaMask.
  • 2. Connect MetaMask and OpenSea.
  • 3. Select an Ethereum piece from the item page.
  • 4. Sign your work on MetaMask and complete the process.

Each of these steps is explained in detail.

Transfer Ethereum to MetaMask

The first step is to send Ethereum to MetaMask.

If you do not yet have a MetaMask account, please click here to open one.

Open your browser and press the MetaMask icon in the upper right portion of the display.

If you do not have Ethereum, you can purchase directly from the button in the image below.

If you already have Ethereum, you can send money using the Send button.

Once the transfer is completed, your MetaMask wallet balance will be updated within a few minutes.

Connecting MetaMask and OpenSea

Next, connect MetaMask and OpenSea.

Access the OpenSea website.

Click on the profile icon in the upper right corner.

Select the MetaMask option from the wallet list.

Click “Next” and enter your email address, user name, etc.

You can always change other parts of your profile later, such as your profile picture, user name, etc.

3. Select an Ethereum piece from the item page

Once you have connected your MetaMask wallet to OpenSea, you will be able to browse the marketplace.

Once you have logged into your OpenSea account, select the piece you wish to purchase.

Sign and complete with MetaMask

Finally, once you have selected your NFT, launch MetaMask (MetaMask) and sign it.

Gas fee will be required for the fee on the Ethereum network.

Once purchased, it will take a few moments to complete.

After a short while, you will be able to view your new NFT in your OpenSea profile and MetaMask wallet.

How to purchase a Polygon work

The next step is how to purchase a Polygon piece.

Polygon is a blockchain that provides scalable, secure and immediate transactions with ethereum currencies such as ETH, USDC and DAI.

Gas fees are only required to transfer Ethereum (ETH) to the Polygon network.

Note that PolygonETH must be used to purchase NFTs on Polygon.

To use Ethereum currency in Polygon, you must first “bridge” them to the Polygon blockchain.

Adding a polygon network to the MetaMask

Next, add a polygon network to the MetaMask.

Click on the tab “Main Ethereum Network” to switch between the connected blockchains.

Scroll down until you find your custom RPC.

Enter the following settings for Polygon’s mainnet

  • Network name: polygon
  • New RPC URL:https://polygon-rpc.com/
  • Chain ID: 137
  • Symbol: MATIC
  • Block Explorer URL:https://polygonscan.com/

Click “Save”.

You are now connected to Polygon’s main network with your Metamask wallet.

Transactions on the Polygon network require the native token MATIC, which is used as the gas charge.

Select a Polygon piece from the item page

The process for selecting a Polygon piece is no different than for an ethereal piece.

Once you find a Polygon piece item, click the big blue “Buy Now” button. 

If this is the first time you have purchased an item with Polygon, you will be asked to unlock the Polygon transaction in your wallet. This needs to be done only once.

Once you sign the unlock transaction, your NFT purchase will be processed quickly.

Moving Ethereum to the Polygon Network

To use Ethereum currency in Polygon, you must first bridge them from the Ethereum network to the Polygon network.

To use Polygon/ETH with OpenSea, you must bridge or transfer Ethereum (ETH) to Polygon (PoS).

To do this, go to the wallet icon in the upper right corner of the OpenSea site.

Once you have ETH in your wallet, click on the three circles on the right. [A “Bridge to Polygon” button will appear.

Clicking on it brings up a pop-up window in which you can enter the amount of ETH to be bridged to Polygon.   

You will be asked to sign the transaction at the wallet, using a MetaMask.

Once the transaction is signed and completed, a confirmation will appear.

The bridging process from Ethereum to Polygon takes approximately 7 minutes. If successful, you will see a purple ETH icon representing the bridged ETH in Polygon (PoS).

Additional confirmation of bridged funds can be found like Etherscan.

If this is the first time you have purchased an item with Polygon, you will be asked to unlock the Polygon transaction in your wallet. This needs to be done only once.

Sign with MetaMask and you are done

Once you have signed your name in MetaMask, your purchase is complete.

Once completed, you will be able to view the purchased NFT works on OpenSea or MetaMask.

Notes on buying at OpenSea

Finally, here are a few things to keep in mind.

Transferring Ethereum in batches to purchase multiple Polygon works

When purchasing a Polygon piece, you will need to move your Ethereum into the Polygon network, as mentioned above.

There is a fee for doing so, so move them together.

It is more time-consuming to send it multiple times and more expensive because the fee is charged each time you do so.

Watch out for scams and fake sales

The second point to watch out for is the sale of fraudulent pieces and fakes.

NFTs remain a risky investment given the growing number of online scams on the Internet, as transactions are completed entirely over the Internet.

Bad websites are easy to spot, and some scam projects may have grammatical or spelling errors on their official websites.

Most reputable projects have established team members who can be contacted.

Check the credibility of the founder, including whether he or she has been involved in similar projects before.

It is not advisable to invest in a project that refuses to disclose the identity of its founder.

Summary of How to Purchase NFTs at OpenSea

This is a summary of this article.

  • There are two types of Ethereum pieces and Polygon pieces.
  • To distinguish between the two, use the ranking, search, refinement, and sorting functions
  • When purchasing a Polygon piece, be aware that you must be connected to the Polygon network
  • When purchasing Polygon works, make sure to send Ethereum in bulk
  • Be aware of fraudulent purchases.

In this article, we have explained how to purchase NFTs on OpenSea, dividing them into Ethereum and Polygon pieces.

Please refer to this article to purchase NFTs on OpenSea.