Cost Calculator
The Cost Calculator is a standalone tool for modelling employment costs before you commit to them. Use it to answer questions like "What would it actually cost to hire someone at £13/hr?" or "How much do we save by hiring an apprentice?" - without affecting any real employee records.
When to Use the Calculator
The Cost Calculator is designed for what-if scenarios:
- Hiring decisions - model the true cost of a new role before you advertise it.
- Pay reviews - see the real impact of a proposed pay rise across different hour levels.
- Comparing candidates - a 19-year-old on NI category M vs a 30-year-old on standard NI at the same base rate will have very different true costs.
- Menu pricing - calculate the cost per working hour (including holiday) to factor into dish costing.
- Budget planning - project annual costs at different weekly hours.
Inputs
The calculator takes the following inputs:
| Input | Description | Default |
|---|---|---|
| Base hourly rate | The contracted rate of pay | - |
| NI category | Standard, M (under 21), or H (apprentice under 25) | Standard |
| Hours per week | Typical or contracted weekly hours | - |
| Pension rate | Employer contribution percentage | 3% |
| Pension opt-in | Whether the employee is enrolled in the pension scheme | Yes |
Use NI category M for employees under 21 and H for apprentices under 25. Both attract a much higher employer NI threshold (£967/week vs £96/week), which can dramatically reduce your costs. StaffBrik will show you the exact saving.
Outputs
Shift Cost (for Rota Costing)
This is the cost per hour excluding holiday accrual. Use this figure when costing your rota, because the rota covers working hours only - holiday cost is a separate liability.
Shift cost = Base rate + Employer NI + Pension
Cost Per Working Hour (for Menu Pricing)
This is the full true cost per hour, including the 12.07% holiday accrual. Use this figure for menu pricing and financial planning, because it represents the total cost of every hour of productive work.
Cost per working hour = Base rate + Employer NI + Pension + Holiday accrual
The difference between these two figures matters. If you use the shift cost for menu pricing, you will underestimate your labour costs because you are not accounting for the fact that employees earn holiday pay on top of their working hours. Always use the cost per working hour for pricing decisions.
Complete Breakdown
The calculator displays a full breakdown of each cost component:
- Base rate per hour
- Employer NI per hour (with the calculation shown)
- Pension contribution per hour
- Holiday accrual per hour (12.07%)
- Total shift cost
- Total cost per working hour
Annual Projections
The calculator automatically projects annual costs at three standard weekly-hours levels:
| Hours/Week | Use Case |
|---|---|
| 20 hours | Typical part-time (e.g. a cafe assistant working mornings) |
| 30 hours | Mid-range (e.g. a sous chef on a 4-day week) |
| 40 hours | Full-time (e.g. a restaurant manager) |
Each projection shows:
- Weekly cost
- Monthly cost (weekly x 52 ÷ 12)
- Annual cost (weekly x 52)
This helps you see the full-year impact of a rate, not just the per-hour figure.
When budgeting for a new hire, use the annual projection at their expected hours. A £12/hr hire working 30 hours a week costs over £21,000/year in true cost - significantly more than the £18,720 you might estimate from the base rate alone.
Comparison Mode
Comparison mode lets you model 2 to 5 different rates side by side. This is invaluable for:
- Pay reviews: Compare the current rate against 2-3 proposed increases and see the true cost difference.
- Hiring decisions: Compare a senior hire at £14/hr vs two part-time hires at £11.50/hr.
- Age-related savings: Compare the same rate under different NI categories to see the impact of hiring younger workers or apprentices.
Example comparison:
| Option A | Option B | Option C | |
|---|---|---|---|
| Base rate | £11.44 | £12.00 | £13.00 |
| NI category | Standard | Standard | M (under 21) |
| Hours/week | 30 | 30 | 30 |
| Shift cost/hr | £13.39 | £14.09 | £13.39 |
| True cost/hr | £14.77 | £15.54 | £14.62 |
| Annual cost | £23,041 | £24,242 | £22,807 |
In this example, Option C (£13/hr with NI category M) actually costs less annually than Option A (£11.44/hr standard NI) despite the higher base rate, because the employer NI saving on a young worker is substantial.
The calculator provides estimates based on current UK tax thresholds and rates. Thresholds change annually (typically each April). StaffBrik is updated to reflect the latest rates, but always verify against HMRC guidance for formal payroll purposes.