More than 300,000 Mormons are registered to do indexing work on images available online.
Three hundred million names are being indexed each year.
But the need is huge and growing dramatically larger and faster than the current crop of volunteer indexers can handle.
"We really need millions (of volunteers)," said Paul Nauta, FamilySearch manager of public affairs. "We're grateful for whatever help we get so with that in mind, we say, 'Thanks, but we need more.'"
Nauta said the indexing program is the largest volunteer initiative of its kind and is making a major difference for genealogists as the key life events of billions of people are preserved and shared for free.
"We get platitudes all the time from people who've searched for a particular name or family for decades. Suddenly they've found the information. We know that's coming from the indexing effort," Nauta said.