Manufacturing & assembly
Check line balance and the bottleneck station.
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Staffing Calculator
How many people do you need for this shift?
How to use this estimate
How many employees do I need for a shift?
Divide the required output by the output one person can complete in the same period, then round up. Use the calculator above to compare that estimate with the people assigned.
Staffing formula
For volume work, multiply each quantity by its time per item, add the minutes and divide by the paid minutes really available per person (paid time × the share left after breaks, meetings, walking and handovers). For a ratio, divide how many are looked after at once by how many one person can look after. For calls and chats, use Erlang C. Round up at the busiest period, then apply the minimum crew if it is higher.
Worked example: 1,000 accepted inspections
Fictional example: demand is 1,000 accepted inspections, the rate is 30 inspections per productive labor hour, each person is paid for 8 hours, and 85% of that time is productive. One person can complete 30 × 8 × 0.85 = 204 inspections. Divide 1,000 by 204 and round 4.90 up to 5 people. With 4 people assigned, estimated capacity is 816 inspections and the staffing gap is 1 person.
Office example: 240 order entries
Fictional example: each comparable entry needs 6 minutes, equivalent to 10 entries per productive labor hour. Enter demand 240, 8 paid hours, 75% productive time and 4 people assigned. Productive time is 6 hours per person; capacity is 240 entries, required staffing is 4 and the estimated gap is zero. This arithmetic baseline does not cover demand peaks, skills or minimum coverage.
Staff ratio calculator: one person per so many
When work is looking after people or things at the same time, the ratio sets the number. Fictional example: a ward of 28 patients with one registered nurse per 5 needs 28 ÷ 5 = 5.6 nurses at all times. Covering their breaks with 88 % of time available gives 5.6 ÷ 0.88 = 6.4, so 7 nurses on the shift. The same works for childcare, care homes and IT support: 850 users with one desk-side technician per 300 users need 3 technicians, 4 when breaks are covered. Use the legal minimum ratio where one applies.
Contact centre staffing with Erlang C
Calls and chats arrive at random, so averages under-staff. Fictional example: 100 calls in 30 minutes with a 3-minute handle time is 10 hours of talk in 5 hours, so the average says 10 people. To answer 80 % of calls within 20 seconds, Erlang C needs 14 people answering: 13 would answer only 79.6 %. Divide by the time available (for example 78 % after breaks and training) to know how many to schedule.
Demand peaks: why the shift average under-staffs
People are needed when the work arrives. Fictional example: hotel housekeeping has 70 hours of rooms and public areas in an 8-hour shift with 85 % of time available, so the average is 11 people. But checkouts bring 17 % of the day’s work into each of the two busiest hours: those hours need 15 people. Split the shift into periods and plan for the busiest one, or move work out of it.
From people per shift to people to employ (FTE)
A shift crew is not a headcount. People to employ = people per shift × shifts per day × days open per week ÷ (days each person works × (1 − absence)). Fictional example: 9 people per shift, 2 shifts, 5 days, people working 5 days and 12 % absence for holidays, sickness and training: 9 × 2 × 5 ÷ (5 × 0.88) = 20.5 FTE, so 21 people. With 17 employed, 4 more are needed.
Skills: when only some people can do the work
A total that looks covered can still fail if the right people are missing. Fictional example: an assembly line needs 9 people at its busiest hour, 3 of them for testing and rework, but only 1 person on the shift is qualified to test. Count each skill’s need at its own busiest period against the people qualified on the shift, then train, re-schedule or hire for the skill that is short.
Choose comparable inputs
Use demand and paid hours for the same period. Enter individual labor time or rate, not a whole line’s output. Different task units are combined as labor minutes, with interchangeable-skills and work-mix assumptions. If the rate already includes breaks and delays, use 100% available time or convert the rate; do not remove the same time twice.
Does this replace a staffing plan?
It is the arithmetic core of one: people per shift at the busiest time, each skill’s cover, and the people to employ once absence is included. Before you commit, check legal ratios, working-time rules, shared people, bottlenecks and how reliable your volumes are with the people who do the work.
Checks for your type of work
Warehouse & logistics
Picking rates vary by zone. Use separate tasks for different zones or work.
Healthcare & care
Legal, policy and clinical coverage rules override this arithmetic estimate.
Restaurant & hospitality
Size coverage for the peak period, not the daily average.
Housekeeping & cleaning
Include travel between rooms or areas once in the task time.
Retail store
Floor coverage, checkout and stock work may need separate tasks or minimum crews.
Contact center & service desk
This workload estimate does not size a queue to a service-level or waiting-time target.
Office & back office
Separate schedulable batch work from urgent work that needs immediate coverage.
Field service & maintenance
Include travel and preparation in the job time without subtracting them twice.
Custom
Use your own measured workload and check the operating constraints.