When it comes to raw dollar amounts, there are basically two numbers that matter.
Below $1.25 a day you hit extreme poverty, which is what about 16% of the world is dealing with. Extreme poverty is the level at which it is almost impossible to meet even basic needs for nutritious food, clean water, basic health care for easily preventable diseases, etc.
The other important number comes around $5,000, which is an average income that correlates to a lot of positive change. This is the number where money stops being so important to happiness. Dip below $5,000, and people start becoming very unhappy very quickly. Above $5,000 and more money still makes people happier, but not really all that much. $5000 is also the point where life expectancy and drops in fertility start leveling off. It should be kept in mind that this is not a magic number- a lot of these effects can be the result of the social organization that allows GDP per capita to get that high- but it does seem to be a critical point where you start getting in on the benefits of the modern world.
Other than that, money really is besides the point. Poverty outside of these bounds is about your place in society. It is about your access to society. The real crime of poverty is not that you don’t have X amount of dollars in your hand. It’s that you are not able to be a part of the things that make us human- meaningful work, family, social organization, and hope.
Are you able to spend time with your family, or are you working triple shifts at McDonalds or stuck in a coal mine hostel? Do you have security, or is your neighborhood full of gangs? Are you scared your children will join gangs, or are you pretty sure they’ll have a nice future? Are you able to join a church, social group, or other community activity that you find meaningful, or are you too sleep deprived and haggard to have social interaction outside of work? Does your work require that you get demeaned or abused? Are you able to learn new things? If something bad happens to you, can you seek justice? Are you able to participate in at least some leisure activities? Can you learn new things? Could romantic love be a part of your life? Do you get to choose who you marry, or refuse sex if you want toIf you are addicted to something, do you have access to treatment?
These kinds of questions are the real questions that determine the toll of poverty. There are some things that the poor in the US have pretty good. We can generally, for example, vote or access education for our children.
In other ways, the US has it worse. A mother who works two jobs to squeak by is going to have next to no social life or interaction with her family. This is a sharp contrast to a somewhat-above-the-extreme-poverty-line mother in Cameroon who works hard in the home, but has never missed a baby’s first step, and has a full social life with her neighbors. A poor family in China probably doesn’t face violent crime in the way they would in a US inner city, and generally is less likely to have to worry about their sons becoming killers and drug dealers.
Anyway, it’s a complex thing, and there are a lot of ways of thinking about it. The world is a funny place. One of the top thing that North Korean refugees express when they have spent some time in South Korea is…a desire to go back to North Korea. North Korea sucks as much as anything can suck. But in South Korea they are on the bottom of the social totem pole, alone, unmarriagable (poverty related stunting makes it hard for the men to find partners), working the worst jobs for bare minimum wages, devoid of the beliefs and sense of mission that they grew up with, and without the social context of their family, they often hate their new lives, as material comfortable as they may be.