RSVP Attendance Calculator
How many guests will actually come, from the yeses, the nos, the people who have not replied and the share who say yes then do not show — with a low-to-high range and a catering number that carries a buffer.
A yes is not a guest: a share of them will not turn up, typically 5 to 10% for a wedding and 20 to 40% for a free event.
How the rsvp attendance calculator works
A yes is not a guest: a share of them will not turn up, typically 5 to 10% for a wedding and 20 to 40% for a free event. The people who have not replied are worth a guess at their yes rate from past events, and the same no-show discount applies to them. Expected attendance is the yes count and the pending count, each scaled, and the range comes from the uncertainty in both. Cater to the expected number plus a buffer, not to the invitation list.
Formula: expected = (yes + pending × pending-yes rate) × (1 − no-show rate) × (1 + plus-ones)
Worked examples
| Inputs | Expected attendance | Note |
|---|---|---|
| 120 yes, 40 pending | 128.8 | about 129 |
| A free event | 92.4 | far fewer than the yeses |
| With plus-ones | 193.2 | half again |
FAQFrequently asked questions
What no-show rate should I assume?
Five to ten per cent for weddings and paid events, 20 to 40 for free ones, higher still for casual online registrations. Your own past events are the best guide.
How should I treat people who have not replied?
As a probability, not as yeses or nos. Half is a fair default; chase them, because every reply narrows the range.
How many should I cater for?
The expected number plus a small buffer — five per cent is typical. Catering for the invitation list wastes a third of the food.
What about plus-ones?
Enter the average extra guests per attendee. A wedding where everyone brings a partner is 1.0; an event with occasional guests is 0.1 to 0.3.
When should I finalise numbers?
When the pending share is under about 20%. Before that the range is too wide; after the caterer's deadline the number is the number.
Where these figures come from
- US FDA Food Code — food service guidance — holding and service context behind catering quantities
- UK Food Standards Agency — the UK food regulator
Last checked: September 2026. Portion and spacing figures are standard catering and event-industry conventions, stated on each page.