Facebook is rolling out a new feature to help blood donors, and the people who need it in India find each other.

On Oct. 1, India's National Blood Donor Day, Facebook will start prompting users to sign up as blood donors. People will see the prompt in their timelines, and can tag themselves as donors in their profiles, and choose to share this with friends.

Image: FACEBOOK

In the weeks after, it'll then allow people or organisations seeking blood to create posts to request for it. The post can be geotargeted, so it pushes a notification to tagged donors who are nearer to the seeking party.

Image: FACEBOOK

When donors accept the request, organisations will be able to reach them privately via phone call, or Facebook's Messenger and WhatsApp platforms.

Facebook says this feature is serving a real need. India faces a blood shortage, where it has about 10 percent less donated than it needs. More than 38,000 donations are needed each day to address the deficit for the hundreds of millions of major surgeries that are carried out.

"People are using Facebook literally thousands of times a week to look for blood donors," Hema Budaraju, a Facebook product manager, told CNN.

The feature will first come to Android apps and the mobile web version, which are the ways most Indians interact with Facebook.

Facebook is inviting people in India to go to facebook.com/donateblood to sign up for the good cause.