How many kids to invite
For a young child, invite their age plus one. For an older child, invite a few close friends or the whole class. Tell us your party and we give the number to invite and the headcount to plan for.
Festidy's free invitation counts the kids and the grown-ups in every reply, so your headcount fills in as answers arrive and you can trim or add to your list.
Make my party planHow we calculate
- Age plus one: your child's age plus one. The American Academy of Pediatrics' HealthyChildren.org calls it "the rule of thumb for babies and toddlers", and Emily Post calls it "still a good one". It is a rule of thumb, not a law.
- A few friends: 4 kids. That is our pick for "a few" (3 to 5).
- The whole class: the class size minus your child.
- Kids who will likely come: 70 to 80 percent of the kids you invite. This is a rule of thumb that many hosts plan on. We looked for a study and did not find one, so treat it as a planning habit and use your real replies once they come in.
- Grown-ups who stay: one for each child who comes when your child is under 6. Happiest Baby says drop-off parties typically start at age 6 or later. From 6 on we count none, though some will stay.
- Headcount to plan for: kids coming (we round up, using the 80 percent end), plus the grown-ups who stay, plus 2 hosts.
- Your limit: if you give a cap or a budget, we find the longest list that fits it. The budget is spread at a guest, Festidy's Standard level for a kids' birthday, and every person in the headcount counts.
- Fairness: Emily Post says to invite everyone in the group if you can, and not to hand out invitations at school if you invite only some. "Whole class, or fewer than half the class" is our own rule of thumb, because a few left out is what kids notice most.
Last updated October 21, 2026. Free, no sign-up.
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Tips for the guest list
- Keep little parties small. HealthyChildren.org warns that big crowds can overwhelm young kids. For a 2 or 3 year old, 3 or 4 friends is plenty.
- Decide on siblings before you send invitations. Say on the invitation whether brothers and sisters are welcome, and count them in the headcount.
- Hand out invitations away from school unless the whole class is invited. Text parents, mail it or hand it over at pickup.
- Ask for replies 10 days ahead. Festidy's invitation does this by default. Then keep the answers in the RSVP tracker.
- Ask about allergies on the reply so you can plan the food and the cake.
Questions
How many kids should you invite to a birthday party?
For a toddler or preschooler, their age plus one. For school-age kids, a few close friends or the whole class, and your space and budget set the top number. This calculator also shows how many will likely come and how many grown-ups to plan for.
What is the age plus one rule for birthday parties?
You invite as many kids as your child's age, plus one. A child turning 4 gets 5 guests. HealthyChildren.org gives the same examples for babies and toddlers.
Should you invite the whole class to a birthday party?
Emily Post says to invite everyone in the group if you can. If you invite only some, do not hand out the invitations at school. Our rule of thumb is the whole class or fewer than half of it.
How many invited kids actually come?
Many hosts plan on 70 to 80 percent. We did not find a study behind that number, so it is a rule of thumb. Ask for replies and use the real count as soon as you have it.
Do parents stay at a birthday party?
For kids under about 6, most parents stay, so plan a seat and food for one grown-up per child. Drop-off parties typically start at age 6 or later.
How many guests can I afford for a kids' party?
Festidy's Simple level is about a guest and Standard about . Divide your budget by one of those and count grown-ups too. For example, $300 at the Simple level covers about 20 guests in all.