Shares of the Ottawa company were climbing 5.2% to $1,216.75 in premarket trading.
Shopify reported net income of $1.26 billion, or $9.94 a share, a swing from a year-earlier loss of $31.4 million, or 27 cents a share.
Adjusted net income came to $2.01 a share, while the FactSet consensus forecast called for income of 74 cents.
Revenue totaled $988.6 million, up 110% from a year ago, and beat analysts' consensus estimates of $859 million.
Gross merchandise volume from merchant customers climbed 114% to $37.3 billion.
"Merchant sales growth on our platform accelerated in the first quarter as merchants leveraged our modern commerce technology, which helps them compete in any retail environment and engage directly with their customers wherever they are," Harley Finkelstein, Shopify's president, said in a statement.
Subscription solutions revenue was $320.7 million, up 71% year over year, primarily due to more merchants joining the platform.
Looking ahead, Shopify said it continues to expect to grow revenue rapidly in 2021, but at a lower rate than in 2020.
The company said the revenue spread may be more evenly distributed across the four quarters than it has been historically if the rollout of the COVID-19 vaccine shifts more consumer spending to services and offline shopping toward the back half of the year.
"We continue to expect rapid growth in gross profit dollars in 2021 and plan to reinvest back into our business as aggressively as we can, with the year-over-year growth in operating expenses accelerating each quarter throughout the rest of the year," the company said.
As such, Shopify said, "we expect full year 2021 adjusted operating income to be below the level we achieved in 2020."