How many people where left homeless in the Japan earthquake?

Answer 1

There are tens of thousands of earthquakes in Japan each year; without reference to a particular earthquake, the question cannot even be approached.

However, even with reference to a particular earthquake, the answer would vary widely, depending on the operational definition of "saved" employed. At the crudest, one could define "saved" as "not killed or injured." This would mean that all of the people were saved in nearly every earthquake.

Furthermore, earthquakes per se are generally not dangerous for most people (although the sudden onset of most earthquakes could cause damaging or fatal stress in those with heart problems): most of the danger to people comes from collapsing structures or from the secondary effects of phenomena like tsunami caused by earthquakes.

Answer 2

The total causalities is not certain yet, but is in the thousands, and at least 80,000 missing people.