Guest list and party length
Enter your child's age. You get how many kids to invite, how long the party should run, when to start and how many grown-ups to expect.
Next: lay out the whole party with the party schedule maker.
Festidy's plan turns the guest list into invitations with an RSVP link and counts the food from the replies.
Make my party planHow we calculate
- Kids to invite, ages 1 to 6: the child's age plus one. A popular rule of thumb, not a law.
- Kids to invite, ages 7 and up: a range, because the best list depends on the class and the child. Our own rule of thumb: 6 to 10 kids for ages 7 to 9, 5 to 10 for ages 10 to 12 and 4 to 8 for teens.
- Length: 90 minutes for ages 1 to 3 and 2 hours for most kids' parties, the same lengths Festidy's planner uses. Our addition: about 2.5 hours for teens.
- Start times: late morning or early afternoon, between mealtimes, so snacks and cake are enough (the advice in Festidy's planner). The clock times, 10:30 AM and 2 PM, are our suggestion; we use 10 AM for ages 1 to 3.
- Grown-ups: kids are about 60% of guests at a kids' party and grown-ups about 40%. So 12 guests is 7 kids and 5 grown-ups. Our addition: for ages 1 to 3, we expect at least one grown-up for every child.
- Space at home: our rule of thumb of 10 to 15 square feet a guest. A 12 by 12 foot room is 144.
Last updated October 21, 2026. Free, no sign-up.
A free birthday party planner keeps the invitation, the replies and the shopping in one place.
Tips for the guest list and the clock
- Count the grown-ups. For little ones, plan on parents staying and count them for food. From about age 7, many kids are dropped off, so you may need only a few helpers.
- Decide the school question first. If you hand out invitations at school, check whether the school expects the whole class to be included.
- Ask about siblings before you invite. An open "siblings welcome" can double a small party.
- End while everyone is still having fun. Save the cake and favors for the end so kids leave on a high.
Questions
How many kids should I invite to a birthday party?
For young kids, the child's age plus one: 6 kids for a 5-year-old, 4 for a 3-year-old. It is a rule of thumb, not a law. From age 7 up, plan on a range such as 6 to 10 kids.
How many kids should I invite to a first birthday?
The age-plus-one rule gives 2 kids. A first birthday is mostly family and close friends, so start with the grown-ups and count them for food.
How long should a kids' birthday party be?
Two hours is the sweet spot for most ages. For ages 1 to 3, 90 minutes is enough, since little ones tire quickly.
What time should a kids' birthday party start?
Late morning or early afternoon, between mealtimes, such as 10:30 AM or 2 PM. Then you can serve snacks and cake instead of a full meal.
How many grown-ups should I expect at a kids' party?
About 40% of your guests: 12 guests is 7 kids and 5 grown-ups. At a drop-off party for older kids, fewer will stay, but this is a safe number for food.
Do I have to invite the whole class?
Not always, but check what your school expects if invitations go out there. For ages 7 and up, a smaller group of 6 to 10 close friends is a common size for a party at home.