Sept 13 (Reuters) - Toast Inc is aiming for a valuation of more than $16 billion in its U.S. initial public offering (IPO), according to a regulatory filing on Monday by the startup that sells software to help restaurants with both online and in-store orders. Boston-based Toast plans to sell 21.7 million shares in the offering, priced between $30.00 and $33.00 per share. At the top end of that range, the IPO will raise $717.4 million. The 10-year-old company provides a software platform that helps restaurants manage online ordering, operate an on-demand delivery network and integrate payment. Its listing plan comes during a pandemic-driven boom in demand for food delivery services that has boosted businesses of DoorDash Inc (DASH.N) and rivals Uber Eats (UBER.N) and Grubhub. Several other high-profile start-ups, including Freshworks, Thoughtworks and ForgeRock, are also slated to go public this fall in one of the hottest years for IPOs. Toast has shifted focus to products such as delivery networks and contactless payment after the hit from the pandemic forced it to slash its workforce by half in the early days of the crisis. Valued at about $5 billion in a private round in February, the company"s investors include TPG, Tiger Global Management, American Express Ventures, Bessemer Venture Partners, G Squared, TCV and Greenoaks. It will list its stock on the New York Stock Exchange under the symbol "TOST." Goldman Sachs & Co. LLC, Morgan Stanley and J.P. Morgan are the lead underwriters for the offering.