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
Monthly retainer
$5,622
Effective hourly rate
$140.56
Monthly gross profit
$3,422
Total contract value
$33,733
Suggested overage rate per hour
$175.69
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter contracted hours per month.
- 2Enter your delivery cost per hour ($).
- 3Enter target gross margin (%).
- 4Enter scope creep buffer (%).
- 5Enter contract length in months.
- 6Read your monthly retainer on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Retainers die from scope creep, not from bad pricing. Build the buffer in from the start: price the hours you expect, plus the overflow hours you know will happen.
Worked example
Using the values the calculator loads with:
Inputs
- Contracted hours per month: 40
- Your delivery cost per hour: 55 $
- Target gross margin: 55 %
- Scope creep buffer: 15 %
- Contract length in months: 6
Results
- Monthly retainer: $5,622.22
- Effective hourly rate: $140.56
- Monthly gross profit: $3,422.22
- Total contract value: $33,733.33
- Suggested overage rate per hour: $175.69
What each field means
Inputs
- Contracted hours per month
- The contracted hours per month used in the calculation. Starts at 40 so you have a working example on load.
- Your delivery cost per hour ($)
- The your delivery cost per hour used in the calculation, measured in $. Starts at 55 $ so you have a working example on load.
- Target gross margin (%)
- The target gross margin used in the calculation, measured in %. Starts at 55 % so you have a working example on load. Accepted range: 0–90 %.
- Scope creep buffer (%)
- The scope creep buffer used in the calculation, measured in %. Starts at 15 % so you have a working example on load. Accepted range: 0–50 %.
- Contract length in months
- The contract length in months used in the calculation. Starts at 6 so you have a working example on load.
Results
- Monthly retainer
- 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.
- Effective hourly rate
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly gross profit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total contract value
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Suggested overage rate per hour
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the monthly retainer pricing calculator work?
Retainers die from scope creep, not from bad pricing. Build the buffer in from the start: price the hours you expect, plus the overflow hours you know will happen. The underlying maths is: Retainer = (Hours × Cost rate) ÷ (1 − target margin) × (1 + creep buffer).
What do I need to enter?
5 values: contracted hours per month, your delivery cost per hour, target gross margin, scope creep buffer, and contract length in months. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the monthly retainer result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
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). Retainer Pricing Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/retainer-pricing
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/retainer-pricing" target="_blank" rel="noopener">Retainer Pricing Calculator — RevenueLab</a> (2026).</p>
Source: [Retainer Pricing Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/retainer-pricing) (2026).