The campaign to give philanthropy its own seasonal day—like Black Friday and Cyber Mondayhas quickly taken off, especially on social media.

Giving Tuesday is only on its third year, but it's quickly become a sensation with non-profits, donors and charitable causes. It's engaged more 13,000 non-profit and corporate partnersfrom Microsoft and PayPal to CVS Health and Toys R Usand the Red Cross and countless other charities. While numbers are hard to come by since the charities and pledges are so diverse, organizers say the campaign has increased awareness and donations to charity.