In my state you pay 17% of your gross income for one kid - unless the combined income is high, then they calculate it differently. 

Is it 25% of gross or net income? That seems on the steeper side of CS.

DH has EOWE only on paper, but he has gotten half of summer and holidays in recent years. DH pays $1000 per month, even with OSS in college. He also pays cell phones, health insurance, car insurance for OSS, and college accounts. He also-also pays for all the boys' clothes, school supplies, school trips, etc. 

Our state recently changed guidelines and is pretty fair. Child support is based on an actuarial table based on what the child's standard of living would be if the parents were still together with their current income. The math isn't entirely clear, but it is regressive: as one's income goes up, the percentage of income allocated to the child's needs decreases, even as the real amount goes up. CS ends at age 18 or high school graduation, with few exceptions. 

DH and BM have 50/50, and he's the higher earner, so he pays her the difference on the amount he owes her and the amount she owes him. The health insurance premium that he pays (that I pay, actually) is also deducted from what she receives. 
Even though DH makes about twice BM's income, it only calculates to him paying a few hundred a month in CS for three kids. School fees, medical bills, and agreed-upon activities are split in OFW with him paying a slightly higher percentage, and everything else is discretionary.

We're in an income shares state.  Meaning income a + income b = total income to spend on kids.  Yay!

The state assumes 17% of that total income is what is necessary.  

Support ends the month the child turns 18 or graduates high school, whichever is later.

If incomes are equal but time sharing is not, the parent with less time pays the other.

If time sharing is equal but income is not, the higher earning parent pays the other.

There are some states that are a flat percentage of the noncustodial's income regardless of custodial income.

There's also a third method used in the US that I can't remember the name of at the moment, but its something like only 4 or 5 states that use it. 

The vast majority are income shares states, though, 40 some odd states use an income shares model.

SO has 50/50, covers health and life insurance, as well as a majority of extracurriculars (greater than the income percentage) and pays roughly $500/mo with an income split hovering 60/40.

*edit, for 2 kids

It totally depends on where you are- in my state you can pay UP TO 50% of your income to CS. However there are calculators that are available and it is reduced based on overnights that they have.

Personally I think there should be very little if any CS if the schedule is 50/50.

In WA, there is an calculator based on the income of both parents. They look at the combined income of both parents and then figure out the percentage of the total each parent should cover, who the custodial parent is, subtract things like health insurance costs, and then set a CS amount. That said, lawyers can "adjust" those and if both parents agree to an amount that will be the set amount, even if it is outside the calculation. 

For us, DH (who makes far less than BM) is paying about 20% of his net income for two kids. This is because he agreed to a higher amount at the last mediation because he wanted something in return (something that BM has already said she won't keep to the agreement on). BM's lawyer practically jumped up with glee when he offered it, because he had already worked with BM to hide a lot of her income (long story and DH had a terrible lawyer). 

I thought that 25% of total income was the max that someone could pay in WA state. Do you have the worksheets from the original divorce decree? If you can afford a consultation, it might be worth talking to a lawyer to see if it would be worth it to try to lower the amount. 

I see all this and it's astonishing. 

My formerSO pays about 0.07% of his income, pays nothing to medical expenses, is supposed to carry medial/dental (he has other kids on a plan already so it would cost nothing extra) but he doesn't and nothing toward daycare. 

My oldest son's dad paid nearly nothing until he was 17.5yrs old. His child support was based on minimum wage since he "didn't have a job". Once my son turned 18, the next day literally, he got a job working has a union pipefitter. My son is 24 and his arrears balance outrageous still. Interest is not charged, so effectively I am forced to give him a $50k+ interest free loan for 15years. 

I guess I have gotten crappy CS workers... or they got lucky. 

ETA: Both chose to have zero custody time. 

I have 50/50 custody of mine and when we divorced, my ex and i had similar incomes. No child support and we each claim one kid each year on taxes. We are supposed to split all costs equally, but it is on the one who accrues the expense (me) to collect. The only good thing i can say about it is that i have never depended on him, and when the kids turn 18 i don't have to worry about how i will support myself. I have friends who literally can't pay their mortgages when their kids age out, and one friend pretty much married another guy when hers aged out so she would have a roof over her head. 

My SO divorced his wife when she was not working and he made about 100k. He pays $1000 per month for two of them, for 50/50 on paper. Though, the kids are with him about 80% of the time. At the time of his divorce, he was also still paying about 2k per month to his first ex wife for his 2 girls, who lived with her in another state and visited him about 6 weeks per year. After one of the girls turned 18, she suddenly couldn't get along with mom and moved in with him (so cliche.) That daughter is now 20, really struggling, and staying with a grandmother because she then couldn't follow any rules at his house.

I am in the southern USA. 

Dup

DH has 50/50 and is not paying CS.  If he was EOWE, in our state he would pay 25% of his gross income for CS, as there are two SDs.  It would be 17% for one kid.  Even if you have 50/50 you could be expected to pay CS in our state.  The formula is a little more complicated than this, but essentially the higher earner would pay 25% of the difference between his/her income and the lower paid parent's income for 2 kids.  We buy everything the skids need at our house, and BM buys everything they need at her house.  They're on our state's CHIP program for insurance, and any extra medical/dental expenses, and activities, are split 50/50.

We are in California, with 50/50, which for tax purposes is 51/49.

When they got divorced, she agreed to no child support, as long as he worked on her car (free labor and ust pay for materials), did ALL transportation, plus pay all medical, while she provides the health insurance.

Not even 2 weeks after we got married, she filed for a "child support modification", whereby she wanted to up the (then) spousal support from $300 to $500, as well as requested $500 for 1 child.

She won $347 in child support as well as the rights to claim child on taxes, so 51/49. They based it off of parents income, visitation time and who provides the insurance.

This was 2 years ago. NOW, she hasnt worked in a few years, visitation is50/50, and DH is starting to ask her to do SOME trasnport (pre-COVID). DH hasnt wanted to take her back to court for any modifications. He thinks his CS would go up, because she isnt working. She stopped working because her job laid her off. Shes been "working" on a court case for an old head injury. So we have been told via SD14 that she "won" her case and got more money. 

SO, we dont take her back to court, because we dont know if she would win and we dont know if he would owe more and we dont know what her income is...

%25 seems high.

Was working then...

Yes, its low, so hence we do not go back to court, and thats why we try not to "anger the beast" so she will keep us out of court.

WOW, that sucks. And here I was getting bummed at thinking about the whole amount that DH will have paid once Munchkin is 18 and graduated.

Yeah that's a lot of money. My DH pays 25% too.  It's so much money. And it definitely does not all go to SS14.  I wish there was accountability on how to was spent.