Occasionally someone says something to me along the lines of, "Why do you care so much about this stuff, you're not really Black?"
The question is posed in a variety of ways, some inappropriate, meant only to undermine a position I may hold, but occasionally someone is genuinely curious and/or uninformed as to what does or doesn't make someone Black.
When posed appropriately, I see this as a valid question. It is legitimately difficult to understand the ins and outs of racial identity.
I'm going to lay out my opinion on this topic as best I can, but understand even I have blind spots here.
A couple times a year something will come up in the news or on social media that sparks a conversation that goes a little something like this: "Wait, is [insert name here] Black?"
The most recent example that I can recall as of writing this is the casting of Rashida Jones as the mother in a Black family on the sitcom "Black AF."
For reference, if you don't know, Rashida Jones looks like this:

The internet wen't crazy with a large faction of people screaming "white washing" and calling for a boycott of the show and the network. "Who thought that it would be a good idea to cast a white woman in the role of a black mother?!"
Then people who knew started sharing images of Rashida Jones and her biological father:

At that point many people paused and asked the question: "Wait, is Rashida Jones Black?"
Quick aside here, Ann Perkins is whatever tf she wants to be and if you come for her I'll cut you, she's literally perfect.
These conversations usually come to a head when someone asks, "What criteria qualifies a person as Black? Is it like a % or like a shade chart somewhere?"
It's a more difficult question to answer than you'd think. In a perfect world it wouldn't be a label that exists at all, but the world as it is differentiates people by their skin color and it's not all that straight forward as to who get's labeled what sometimes.
The proof that it's ambiguous is in stories like Rachel Dolezal.
Rachel Dolezal, infamously, was a white woman who faked being Black for years, even becoming the president of a chapter of the NAACP in Spokane, Washington:

That she was able to "pass" as Black even among Black people shows that there is some real complexity to this question.
How do we navigate this then? If Black people don't even know who's Black then who does? Who gets to decide who is or isn't?
This is my best shot at setting the parameters:
Someone identifying as Black is somewhat relative to whether or not they've had life experiences unique to the Black community due to their physical appearance. Someone is Black when the world interacts with them on that basis and they can't do anything about it (i.e. it's not a choice).
I'll elaborate using myself as an example.
This is my ancestry according to one of those websites you give your DNA to so the FBI can frame you for a crime later when needed:

I am a majority European, 52.9%, plurality Irish if you break it down another level. I'm only 44.2% African descent, not even half.
Why in the world do I identify as Black?
A little background on me first for context.
I was raised without my Black father or my Black family present. I grew up in a white household in a middle class neighborhood where there were very few Black people. Nobody ever sat me down and gave me any kind of talk about what it meant to be Black.
I was also fairly insulated from Black culture in general for the majority of my youth. I wasn't able to listen to popular music regularly being raised by my relatively strict christian mother. I attended a small christian school from 4th to 7th grade where I was the only Black kid in my grade level (I actually think I may have been the only Black kid in the whole school at least 1 of those years).
All that to say, everything I feel on this is derived from direct life experience, it was never fed to me through family, friends or the culture I was surrounded by.
I however looked like this in my youth:

I didn't know I was "black" the first time someone called me a nigger. I didn't know I was "black" the first time I got followed around a store. I didn't know I was "black" the first time a father physically chased me away when I came by to say hi to his daughter.
I knew I was black by the time the police were called on me because I was sitting at a park after sunset. I knew I was black by the time my girlfriend (now wife) was called a nigger-lover. I knew I was black by the time people threatened to call the police on me early in my sales career for simply being in their office complex.
I know I'm Black in every single interaction with someone new as I battle the nagging feeling that I'm potentially fighting uphill to overcome their preconceptions of who I am.
Being Black is a lived label.
One of the reasons why there's so much uncertainty in the question of "what qualifies someone as Black?" is that other Black people give the benefit of the doubt to anyone who identifies themselves as Black, assuming that they've had life experiences that have caused them to come to that conclusion.
Let's go back to the original example I cited, Rashida Jones. Consider a time where Rashida is trying to make it in Hollywood early in her acting career. Do variances in her "look" change what types of roles casting directors are considering her for? Of course they do. Rashida Jones is Black because that's how the world interacts with her. I'm sure there are a multitude of instances she would site both personally and professionally.
There is a spectrum here. Rashida Jones doesn't deal with the exact same things that Lupita Nyong'o deals with for example. That doesn't make Rashida Jones not Black.
I don't deal with the exact same things that another Black person who has a darker complexion than me has dealt with in their life (one of the reasons why if I'm in conversation with someone like that I generally shut up and listen), but that doesn't make me not Black.
Being Black is a shared experience, it's not an identical experience.
Quick aside, I feel like it's pertinent to point out if all this sounds a bit convoluted it's because it is. This is all artificial, race is a societal construct not a biological one beyond the fact I don't sunburn as quickly.
For those that plant themselves in the "I don't see race" group, I understand what you're trying to say, but that's not the solution in this moment. You're in an odd time in history where it's not a helpful position to take most of the time, let me explain.
If you were in the 1980s or prior, "I don't see race" is a brave statement to make because the world was unapologetically divided along racial lines. Saying "I don't see race" in those times was a departure from the norm and was likely to be met with some animosity. It took bravery to say it.
If in the future we heal the wounds of racism and get to a point where race is legitimately irrelevant then "I don't see race" is 100% the position that everyone should share.
Between those two periods in time however, while we're in the process of treating the wounds, you need to see race because that's where we need to address the issue. "I don't see race" is a dismissive statement in this specific time we live in. It's a statement that you've washed your hands of the whole thing because you don't want to take the time to understand it, or have determined that it's unsolvable.
The exception here would be if you're among hardened racists, then "I don't see race" remains a brave statement as those people are stuck in the past.
Back to the topic at hand, the natural next question is, "Well then at what point is someone not Black? Can anyone who has any African heritage claim to be Black if they face any hardship?"
There's an often repeated adage that goes, "What's the difference between art and pornography? You know it when you see it." I believe a similar concept applies here.
Que awkward segue into talking about my son...
I would not identify my own biological son as Black currently, nor do I think he is likely to have the life experiences that would lead him to identify himself as such in the future.

He's 22% African descent. You'd likely never know it unless you were looking for it.
Nobody that doesn't know it is ever going to call him a nigger on a guess. His life experiences are not likely to be effected by his African heritage.
The caveat here I keep calling out is life experience. Let's say at some point in his life he moves to neighborhood that's exclusively white where racism still flies. Someone in that town thinks he looks a little different than everyone else, in a different sort of way, they just can't put their finger on it.
That person does a little research, finds out that I'm his father, that he's part Black. The neighborhood then ostracizes him due to his African ancestry. In this example, my son is Black. His life now features an additional layer of difficulty spurred on by things in his physical appearance he has no control over related to his African heritage.
One wrinkle I'll add is that there is a conversation to be had here about learned/generational trauma, i.e. my son will hear stories from me one day on what my experience has been like as a Black man and that may factor in how he wishes to identify himself. I'm not educated enough on that concept to have a strong opinion on it. When he's older I'll have a conversation with him and listen to his perspective.
Finally, there are a lot of side topics that I left on the table here. My acceptance and eventual ownership of my Black identity was not a clean process, it rarely ever is. There's also a conversation around how I handle the rest of my ancestry, i.e. I love playing up my Irish heritage around St. Patrick's day, why that is and how that slots into my overall identity. There's an interesting dialog around the difference in how white and Black people talk to me about this topic. My point being, this is a more complex subject matter than what I've laid out above, I didn't cover all angles here.
That being said, I hope this helps someone better understand the context and complexity around racial identity in the big tent that is the Black community. At least I hope it didn't confuse you even more than you were when you started.
Stay Curious. Please Share.
Always a concern on my end, but immediately alleviated with the Mast family... you guys always welcome me with open arms.
"I know I'm Black in every single interaction with someone new" ..... i hope you didn't feel that way when you met our family.