NEW YORK — Groupon is launching an online scheduling tool so small businesses can let customers book appointments more easily.

The tool launching Monday lets Groupon users book appointments for massages, haircuts, guided tours and other services they purchase deals for. Businesses can also use it to book appointments that are not sold through Groupon Inc.

The Chicago-based online deals company says it is offering the scheduler free of charge to businesses that use Groupon. It will also be free for merchants that sign up in the next three months, even if they haven’t offered any Groupon deals. The company didn’t say how much the service will cost later.

Restaurants and hotels aren’t eligible. Groupon said they usually have their own scheduling systems in place and the tool, called Groupon Scheduler, doesn’t support these types of businesses right now.

The move is part of Groupon’s long-term push to offer services and tools that would encourage small businesses to run more deals through the company.

The tool is based on technology from a Canadian company it bought last fall, OpenCal.

Groupon users will be able to book appointments when they buy a Groupon, or wait till later. They can also change or cancel appointments online. Users can also continue to schedule with the merchant directly.

The tool will let merchants track their customers, including what other appointments they have made and how much they spend during each visit.

First Published March 19, 2012, 1:18 p.m.