Since last year, Uniswap – the largest decentralized exchange on Ethereum – has typically commanded the most in daily transaction fees, a key barometer for actual usage of the world’s second-largest blockchain.

The resurgence of NFTs from highs earlier this year, however, has helped put OpenSea in the top spot with over $1.9 million in gas spent on transaction fees in the past day. By comparison, a combined $1.57 million in transaction fees has been spent on Uniswap V2 and V3.

A slew of NFT projects have been launched in recent weeks, such as Pudgy Penguins, Sad Frogs District and Space Poggers. The projects host different types of auctions that allow users to mint a random NFT for a given amount of ether, the native currency of the Ethereum blockchain.

OpenSea is a secondary marketplace for these NFTs to be bid on and traded. Last month, the marketplace raised $100 million in a funding round led by Andreessen Horowitz.

Data site Glassnode projects that OpenSea could have $1 billion in volume this month with 300,000 unique users.