The queue math of check-in: staffing gates with actual numbers

Every gate crush we've ever debriefed came down to the same mistake: staffing was set by tradition ('we always use six people') instead of arithmetic. Here's the model we use with organizers, and it fits on a napkin.

The napkin model

A trained scanner with a decent QR flow processes 8–12 attendees per minute. Call it 10. If 70% of your 5,000 attendees arrive in the peak 45 minutes — a typical concert curve — that's 3,500 people needing (3,500 ÷ 45) ≈ 78 scans per minute at peak. At 10 scans per minute per lane, you need 8 lanes, plus one for exceptions.

Where the model breaks

• ▸Screenshots and brightness: attendees fumbling for tickets cost more time than scanning. Send day-of reminders that deep-link straight to the QR.
• ▸Exceptions clog lanes: name changes, duplicates, and 'it's under my friend's account' need a dedicated resolution desk, never a scanning lane.
• ▸Offline gaps: if the venue's network drops and your scanners can't validate, every lane stops. Offline-capable scanning with later sync is non-negotiable for fields and basements alike.

Measure it live

A live entry-rate dashboard turns staffing into a control loop: watch scans-per-minute per gate, and shift staff toward the hot gate before the queue forms. Organizers using live occupancy data consistently cut peak queue times by a third without adding headcount.