Walmart.com now boasts 50 million SKUs, and growing, Lore said on a call with journalists, adding that Wal-Mart is very pleased with its growing assortment of food and essentials online. This is up from 35 million items during the previous quarter.
"Looking in more detail at the various strands of Walmart's initiatives, a sharper focus on price is cutting through — especially on grocery," GloablData Retail Managing Director Neil Saunders wrote in an email.
By pursuing its "Everyday Low Price" strategy, Wal-Mart is likely winning over customers who used to shop for food at dollar stores — think Dollar Tree and Dollar General — and mainstream grocers, Saunders said.
"The response to Walmart flexing its price muscles has been good, and we expect further small gains over the rest of this year. A more disciplined focus on low prices is also important as Aldi, and now Lidl, expand into the market," Saunders said, citing data that suggests Wal-Mart is unlikely to need to respond much more aggressively on price than it already has.
Lidl, a German discount grocer, announced Wednesday that its first 20 U.S. stores would open June 15 in the Carolinas and Virginia, with another 80 slated to open within the year. Lidl is known for low prices and its emphasis on store brands.
Wal-Mart didn't offer much more guidance Thursday regarding the breakdown of its online sales for the latest quarter, which surged a staggering 63 percent and added 0.8 percentage points to its first-quarter same-store sales gain.
Lore said the results were driven higher largely by Walmart.com's free two-day shipping offering and higher repeat orders.
Wal-Mart recently rolled out an "Easy Reorder" feature that makes it simple for shoppers to restock foods like Kraft Mac & Cheese and General Mills' Honey Nut Cheerios, or other items they would buy frequently.
Amazon Dash is a similar concept, where customers can restock products by brands like Tide, Glade or Gatorade, with the push of a button.
Meanwhile, Target is trying to stay competitive by stealing Jeff Burt from Kroger to lead its food and beverage business, as comparable sales lag in this division. Last year, Target walked away from an acquisition of Phoenix-based grocery chain Sprouts Farmers Market and instead has shifted resources toward launching its own private-label brands.
"While share loss online and to Amazon.com specifically is inevitable and likely to become more pronounced in time, Walmart has an effective omni-channel approach in place to better compete than peers," Mark Astrachan, an analyst at Stifel, said in a research note.
Wal-Mart shares hit a 52-week high on Thursday, following the retailer's quarterly financial report.
Read: Wal-Mart reports first-quarter earnings