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
You receive
$96.80
Fee per transaction
$3.20
Effective rate (%)
3.20
Monthly fees
$800.00
Charge this to net the full amount
$103.30
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter transaction amount ($).
- 2Enter percentage fee (%).
- 3Enter fixed fee ($).
- 4Enter transactions per month.
- 5Read your you receive on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Processor fees are a percentage plus a flat cent charge, so small transactions hurt the most. This shows net proceeds and the true effective rate.
Worked example
Using the values the calculator loads with:
Inputs
- Transaction amount: 100 $
- Percentage fee: 2.9 %
- Fixed fee: 0.3 $
- Transactions per month: 250
Results
- You receive: $96.80
- Fee per transaction: $3.20
- Effective rate (%): 3.2
- Monthly fees: $800.00
- Charge this to net the full amount: $103.30
What each field means
Inputs
- Transaction amount ($)
- The transaction amount used in the calculation, measured in $. Starts at 100 $ so you have a working example on load.
- Percentage fee (%)
- The percentage fee used in the calculation, measured in %. Starts at 2.9 % so you have a working example on load. Accepted range: 0–10 %.
- Fixed fee ($)
- The fixed fee used in the calculation, measured in $. Starts at 0.3 $ so you have a working example on load.
- Transactions per month
- The transactions per month used in the calculation. Starts at 250 so you have a working example on load.
Results
- You receive
- 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.
- Fee per transaction
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Effective rate (%)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly fees
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Charge this to net the full amount
- 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 card processing fee calculator work?
Processor fees are a percentage plus a flat cent charge, so small transactions hurt the most. This shows net proceeds and the true effective rate. The underlying maths is: Fee = amount × rate% + fixed; net = amount − fee
What do I need to enter?
4 values: transaction amount, percentage fee, fixed fee, and transactions per month. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the you receive 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.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Payment Processing Fee Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/payment-processing-fees
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/payment-processing-fees" target="_blank" rel="noopener">Payment Processing Fee Calculator — RevenueLab</a> (2026).</p>
Source: [Payment Processing Fee Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/payment-processing-fees) (2026).