Zola, an online wedding planning start-up, said Thursday it has raised $100 million in a new funding round.

The series D financing was led by existing investor Comcast Ventures, with CNBC parent NBCUniversal and Goldman Sachs Investment Partners joining among the new backers.

New York-based Zola, which gears its platform to millennials, said total investments now stand at $140 million. The company said it has more than 500,000 users of its planning tools, a one-stop destination for a couples' wedding website, registry, checklist and guest list.

"Zola is a retailer and an e-commerce store," co-founder and CEO Shan-Lyn Ma told CNBC's "Squawk Box." "We work with 600 brands today; many of the brands you might find in a retail store."

But she said couples can also use Zola to raise money for their honeymoons. "Some of our most popular gifts through the registry are the Delta or Southwest [airlines] gift cards."

Ma, formerly a senior executive at the online shopping site Gilt Groupe, would not disclose the current valuation of Zola. But she did say she has lofty goals. "I think the definition of a unicorn, can a company be valued at a billion dollars. Our goal is to be much bigger than that. When you look at the weddings industry, there's never been a multibillion disruptor to emerge."

Zola sponsored the nuptials for "TODAY" show wedding winners Kyle Otte and Jordon Taylor, who tied the knot live on television, with wrestler and actor John Cena officiating. Zola also plans an integration with NBCUniversal's E! Network for the royal wedding.