Walmart (WMT), the world's largest retailer, posted quarterly results Tuesday morning that easily topped estimates, with the wave of elevated consumer spending at the retailer last year extending into the first three months of this year. Shares rose more than 1% in early trading.

Here were the main results in Walmart's first-quarter report compared to consensus estimates compiled by Bloomberg:

• Q1 Revenue: $138.31 billion vs. $131.97 billion expected vs. $134.62 billion Y/Y

• Q1 Adjusted earnings per share: $1.69 vs. $1.22 expected vs. $1.18 Y/Y

Walmart benefited strongly from consumer shopping trends during the pandemic, with customers stocking up on pantry items while restaurant capacity was limited. Shoppers also turned increasingly to big box retailers like Walmart, where they could get all their home goods and groceries in one trip while trying to socially distance.

But Walmart was able to exceed Wall Street's expectations even given last year's tailwinds. The company unexpectedly grew sales over last year, whereas revenue was expected to decline year-on-year for the first time since 2016. Total U.S. comparable sales, excluding gas, rose 6.2% in the first quarter, slowing from the 10.3% rate in the same period last year, but topping consensus analysts' estimates for an only 2.03% increase.

"Our optimism is higher than it was at the beginning of the year," Walmart CEO Doug McMillon said in the earnings announcement Tuesday morning. "In the U.S., customers clearly want to get out and shop."

Walmart's results got an additional boost in the first quarter from its growing e-commerce business and from increased spending after multiple rounds of stimulus checks were distributed to most Americans. Walmart's U.S. e-commerce sales grew 37% in the quarter, maintaining a double-digit growth rate while slowing from the pandemic-era peak of 97% year-over-year digital growth last year.

"We have a strong position as our store environment improves and e-commerce continues to grow," McMillon added. "Stimulus in the U.S. had an impact, and the second half has more uncertainty than a typical year. We anticipate continued pent-up demand throughout 2021."

Walmart also raised its outlook for full-year earnings and sales for the full year. The company now sees net sales growing by low- to mid-single digits, excluding divestitures, after forecasting as low-single digit increase previously. Earnings per share are expected to rise by high single digits this year, whereas a slight decline was forecasted previously.