We each get $100 every 2 weeks.
It's not "enough" to not have to plan, but it keeps us in clothes, haircuts, girls' nights, do dads, and whatchmacallits. (AKA haircut this paycheck, new sneakers next paycheck, new bra the paycheck after, lunch out once a week, etc.)
ALL of our personal expenditures (from the above to subscriptions, memberships, lunches not from the fridge, personal electronics, etc. come from it. We can save our personal money or spend it, as we choose. (It took me a couple years to stack away 2k from that to buy a laptop. $20 bucks every paycheck for 50 paychecks).
The most important thing; in my experience... is that the amounts are EQUAL, whatever the total is. Just for an example: My husband was spending $10 a day on lunches. That's $400 a month right there. Add in his other nickel and dime expenditures (also to mention his "big" ones, $40 here, $60 there) and he was blowing over a thousand dollars a month just on himself. Meanwhile, I hadn't had $10 a month to myself in years. There is NO reason, imho, why one person is "too good" for the same food the rest of the family eats (aka lunch at work). If ya want different lunches, either we'll change the grocery list OR you can buy it out of your personal money.