The Testnet API is used for browsing non-fungible assets on the Sepolia test network. Creating and purchasing assets on this network requires Sepolia ETH, which is free. Here is an example faucet link which you can use to acquire Sepolia ETH for testing.

The API is identical to the OpenSea mainnet API, except the base URL is For mainnet an API key is needed, but for testnets you do not need an API key.


What is the default rate limit?
GET requests are limited to 4/sec. POST requests are limited to 2/sec.

Do I need a Testnets API Key?
No, you no longer need an API key to make requests to our Testnets API endpoints.

What can I build using Testnets?
You can do many things on Testnets! We recommend you start off with the Creating your first NFT smart contract tutorial.

Can I contact OpenSea about the API?
Yes. You can reach out to our developers channel on Discord or email us at [email protected].