According to Jehovah’s Witnesses how many people will live on the earth? According to JW teaching all the dead will be resurrected to earth except the 144k that get heavenly life. There will be a judgement of all these at the end of the millennium.

Estimates by scientists are that perhaps 108 billion people have lived since human life began. If nearly that many are judged righteous will there be enough space on earth for them? Wikipedia states that there are 123 billion acres on earth's surface, including 37 billion acres of dry land.

So either there will be a crowded earth, more dry land will become available or a majority of the resurrected will be judged unrighteous. What do JWs, or others with similar views, expect will be the case?
The official teaching is that the "vast majority" of those who have lived on earth will in fact be resurrected (see Watchtower, March 15, 2006). Jehovah's Witnesses' most recent statements indicate 20 billion as a "liberal estimate" of the number of individuals who have lived on the planet. Based on a 20 billion estimate Jehovah's Witnesses feel that the earth would be capable of comfortably supporting those brought back in the resurrection.

This estimate is mentioned in both the Reasoning From The Scriptures handbook as well as the Jehovah's Witnesses Bible encyclopedia Insight On the Scriptures. (Note both of these publications were published towards the end of the 20th century and no new estimates have been provided since that time; it is likely that both publications will be updated in the years to come and perhaps provide new estimates).

Along the same lines, though not stated dogmatically, it is generally believed that the powers of procreation may be only allowed for a specific period of time for those who survive Armageddon. Once the earth's capacity had been reached these would be rescinded. (see Watchtower, December 15, 2003. 

This concept is based on the supposition that those resurrected will not marry and therefore not bear children (Matthew 22:29, 30). However starting in 2014  the belief of the Resurrected no longer being eligible to marry has been stated with less certainty (see See Watchtower, August 15, 2014