Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total staffing cost
$2,380,800
Teachers needed at target ratio
30
Staffing cost per student
$5,291
Teachers needed at alternate ratio
23
Extra cost vs alternate ratio
$555,520
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How to use this
- 1Enter total students.
- 2Enter target student-teacher ratio.
- 3Enter average salary per teacher ($).
- 4Enter benefits & payroll tax load (%).
- 5Enter alternate ratio to compare.
- 6Read your total staffing cost on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Schools and tutoring centers set a target student-teacher ratio for quality reasons, but that ratio directly drives headcount and payroll. This calculator takes total enrollment and a target ratio, computes required teacher count (rounded up since you can't hire a fraction of a teacher), and multiplies by fully loaded salary cost to show the staffing budget, then compares it against a looser ratio to quantify the cost of smaller classes.
Worked example
Using the values the calculator loads with:
Inputs
- Total students: 450
- Target student-teacher ratio: 15
- Average salary per teacher: 62000 $
- Benefits & payroll tax load: 28 %
- Alternate ratio to compare: 20
Results
- Total staffing cost: $2,380,800
- Teachers needed at target ratio: 30
- Staffing cost per student: $5,291
- Teachers needed at alternate ratio: 23
- Extra cost vs alternate ratio: $555,520
What each field means
Inputs
- Total students
- The total students used in the calculation. Starts at 450 so you have a working example on load.
- Target student-teacher ratio
- The target student-teacher ratio used in the calculation. Starts at 15 so you have a working example on load. Accepted range: 1–40.
- Average salary per teacher ($)
- The average salary per teacher used in the calculation, measured in $. Starts at 62000 $ so you have a working example on load.
- Benefits & payroll tax load (%)
- The benefits & payroll tax load used in the calculation, measured in %. Starts at 28 % so you have a working example on load. Accepted range: 0–60 %.
- Alternate ratio to compare
- The alternate ratio to compare used in the calculation. Starts at 20 so you have a working example on load. Accepted range: 1–40.
Results
- Total staffing cost
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Teachers needed at target ratio
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Staffing cost per student
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Teachers needed at alternate ratio
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Extra cost vs alternate ratio
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why round up teacher count instead of using a decimal?
You can't hire 22.5 teachers. Rounding up to whole headcount is the only way this number is actionable for budgeting, and it means small changes in the ratio can trigger a full extra hire at the margin — worth checking manually near round numbers.
What's a typical benefits load?
Public schools often run 25–35% on top of base salary for health insurance, pension contributions, and payroll taxes. Private schools and tutoring centers can run lower, 15–22%, if benefits are less generous.
How much does dropping the ratio by a few students really cost?
It's nonlinear because of the rounding. Going from a ratio of 20 to 18 might add zero teachers if you have slack in the last class, or it might trigger two extra hires if enrollment sits right at a threshold — always run your actual enrollment number, not a round estimate.
Does this model account for aides or specialists?
No, it's classroom teachers only. Add aide, special education, and specialist staffing as a separate line since those ratios are typically driven by different regulations, not the general classroom ratio.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Student-Teacher Ratio Staffing Cost Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/student-teacher-ratio-staffing-cost
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/student-teacher-ratio-staffing-cost" target="_blank" rel="noopener">Student-Teacher Ratio Staffing Cost Calculator — RevenueLab</a> (2026).</p>
Source: [Student-Teacher Ratio Staffing Cost Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/student-teacher-ratio-staffing-cost) (2026).