Peak and class inputs
One queue or skill at a time.
The first day of your busiest stretch, for example the start of the holiday peak.
Productivity of a new agent as a percent of a ramped one, comma separated. Week 7 and later counts as 100.
The date your class finishes nesting and starts taking live contacts.
Based on your planned floor start date.
Training starts 12 Oct 2026. Floor start minus training and lead time.
| Floor start | Date | Capacity per hire | Hires needed |
|---|---|---|---|
| 6 wks before | 12 Oct 2026 | 77% | 26 |
| 5 wks before | 19 Oct 2026 | 78% | 26 |
| 4 wks before | 26 Oct 2026 | 77% | 26 |
| 3 wks before | 2 Nov 2026 | 76% | 26 |
| 2 wks before (planned) | 9 Nov 2026 | 73% | 28 |
| 1 wk before | 16 Nov 2026 | 67% | 30 |
| Peak start | 23 Nov 2026 | 60% | 33 |
| 1 after | 30 Nov 2026 | 47% | 42 |
| 2 after | 7 Dec 2026 | 35% | 57 |
| 3 after | 14 Dec 2026 | 24% | 84 |
Between 6 and 3 weeks before peak the number barely moves, because the class is mostly ramped either way. After that, every week of delay costs more than the one before.
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Results are estimates for planning purposes only and should not replace professional workforce management judgment.
The model asks how much fully ramped capacity one hire adds across your peak weeks, then divides your capacity gap by that number. A hire who reaches the floor early is ramped for most of the peak, so each hire counts for nearly a full agent. A hire who arrives after the peak has started spends their slowest weeks inside it, so each hire counts for far less and you need more people.
Step by step
- Ramp curve. In floor week 1 a new agent works at the first ramp percentage, rising week by week to 100 percent from week 7.
- Attrition. Each week on the floor, a slice of the class leaves, so later peak weeks count a little less.
- Drop-out. The result is scaled down by training drop-out, because some hires never reach the floor.
- Hires needed = gap divided by capacity per hire, rounded to the nearest whole person.
- Offer-by date = floor start minus training and nesting minus hiring lead time. That is the latest date offers can go out for the planned start.
Using it well
- Replace the defaults with your own training drop-out, ramp and attrition data; the results are a model, not a measurement.
- Get the capacity gap from the Erlang C Calculator or your capacity plan.
- Size the class itself with the Hiring and Class Size Planner.
- If the offer-by date has passed, use the options in the guide before adding more hires.
Frequently asked questions
Why does a later class need so many more hires?
A new agent is slowest in the first weeks on the floor. A class that arrives after the peak has started spends those slow weeks inside the peak, so each hire adds far less capacity and you need more people for the same gap.
What is the ramp curve?
How productive a new agent is week by week compared with a fully ramped agent. The default is 40 percent in floor week 1, rising to 94 percent by week 6 and 100 percent from week 7. Replace it with your own nesting data.
How is the offer-by date calculated?
Planned floor start minus training and nesting weeks, minus the hiring lead time from offer to the start of training. If that date is in the past, the early start window has closed for this peak.
Does this replace my Erlang C staffing calculation?
No. Erlang C sizes the gap in fully ramped agents for each interval. This calculator turns that gap into a hiring number based on when the class reaches the floor. Use the Erlang C calculator first, then bring the gap here.
Related reading: read the full guide on seasonal hiring start dates.
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