Event RSVP Estimate Calculator

Work out event rsvp estimate instantly with clear inputs, formula shown and shareable results.

About Event RSVP Estimate Calculator

Expected attendance is confirmed yeses plus roughly a third of non-responders, reduced by the historical no-show rate. Catering is then ordered slightly above that figure, because running out of food is a far worse outcome than a little waste.

Formula

Attendance estimate

expected = (yes + 0.35 x non-responders) x (1 - no-show rate); cater for expected x 1.05

Worked example

With the default values below, Event RSVP Estimate Calculator returns Expected attendance of 95. Change any input above and every figure here is recalculated in your browser.

Inputs used

People invited: 150 people
Confirmed yes: 96 people
No response yet: 22 people
Typical no-show rate: 8 %

Results

Expected attendance: 95 people
Expected from non-responders: 8 people
Expected no-shows: 8 people
Number to cater for: 101 people

Step by step

1Values used
2Attendance estimate
3Expected attendance= 95 people
4Expected from non-responders= 8 people
5Expected no-shows= 8 people
6Number to cater for= 101 people

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to whole numbers, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

What no-show rate should I assume?

5-10% for a paid event with committed guests, 20-30% for free events, and higher still for casual invitations.

Why do a third of non-responders attend?

Non-response correlates with disorganisation rather than disinterest. The exact fraction varies by event type, so track your own history.