NEW YORK — Giving Tuesday, a 5-year-old phenomenon aimed at encouraging online charitable giving, produced record-shattering donations this week, according to two organizations that tracked the flow of gifts.

The 92nd Street Y in New York City, credited for launching the event in 2012, said Wednesday that contributions reported by organizations in the U.S. and abroad for a 24-hour period total $168 million — up from about $117 million in 2015. It said there were roughly 1.6 million donations, coming from people in nearly 100 countries.

Blackbaud, a software company that serves many nonprofits, reported that it processed $47.7 million in online donations Tuesday for more than 6,700 organizations — a 20 percent increase in giving over last year. It said 22 percent of the donations were made via a mobile device.

In its first year in 2012, under the aegis of the 92nd Street Y, Giving Tuesday generated about $10 million in donations after being pitched as a way to promote charity on the heels of Thanksgiving weekend’s big shopping days. In subsequent years, it has mushroomed into a decentralized global movement, with nonprofits of all types soliciting donations, promoting volunteerism and encouraging acts of kindness.

The 92nd Street Y received detailed reports from many of the participating organizations. Among them:

A Baltimore nonprofit called Thread organized a “Love Notes to Baltimore” campaign where residents wrote uplifting messages in chalk on streets.

Volunteers in Bethel, Alaska, stood in below-zero weather to accept donations for local nonprofits.

The Humane Society of the United States exceeded its target of $200,000, with a total of $350,000 raised.

The University of Michigan raised $5.5 million in 24 hours, compared to $4.3 million last year.

Henry Timms, co-founder of Giving Tuesday, said the event’s success was due to “the work of ordinary people all over the country.”