Why reverse the fee?
Adding the fee percentage directly is usually not enough.
If a 3.4% fee is taken from the final amount charged, adding 3.4% to your target still leaves you short. Gross-up solves the equation from the net amount backwards.
Reverse fee calculator
Invoice Gross-Up Calculator
Enter the amount you want to keep and the fee structure. Earnquo calculates the minimum amount to charge so your net does not fall short.
Use the actual fee charged by your platform or payment provider. Taxes and VAT are not included.
Enter a target above zero, a percentage from 0% to below 100%, and a non-negative fixed fee.
Formula
Built around the final charged amount.
Gross amount = (target net + fixed fee) ÷ (1 − percentage fee). Earnquo then checks cent-by-cent rounding so the result is the minimum amount that still reaches your target.
Worked examples
Gross-up examples using 3.4% + €0.35
The table uses the same cent-level calculation as the live tool. It shows how much you would need to charge to preserve several target net amounts under one simple percentage-plus-fixed fee structure.
Target netChargeEstimated feeFinal net
€100.00€103.88€3.88€100.00
€500.00€517.96€17.96€500.00
€1,000.00€1,035.56€35.56€1,000.00
Why “just add the fee” can leave you short
A common shortcut is to add 3.4% plus €0.35 directly to the amount you want to keep. The processor then charges its percentage on that larger total too. The shortfall is small on one payment, but it becomes repeatable leakage across many invoices.
Target netNaive chargeNet after feeShortfall
€100.00€103.75€99.87€0.13
€500.00€517.35€499.41€0.59
€1,000.00€1,034.35€998.83€1.17
The percentage is charged on the gross amount
Gross-up solves the fee equation backwards. For a percentage fee r and fixed fee f, the starting point is (target net + f) ÷ (1 − r). Earnquo then verifies the result at currency precision so rounding does not leave the target one cent short.
Use the actual fee structure
This generic calculator works best when the charge really can be represented by one percentage plus one fixed amount. Tiered pricing, caps, minimum fees, currency conversion, tax withholding or multiple fee layers require either additional calculation or a provider-specific tool.
Who absorbs the fee is a commercial decision
Gross-up tells you the mathematics, not whether a client should pay the extra amount. Contracts, platform rules, local law and customer expectations can affect whether fees may be passed through. Keep the commercial decision separate from the calculation.
Before you put the number on an invoice
- Verify the provider or platform fee that applies to this exact transaction.
- Check whether currency conversion or cross-border charges are separate.
- Confirm whether taxes or withholding are applied before or after processing fees.
- Keep a small record of the fee assumption used for the quote or invoice.
Related practical guides
Read how invoice gross-up works for the full derivation and how to account for payment fees in client pricing before deciding whether to absorb or pass on the cost. See Earnquo methodology for rounding and source rules.
Calculator guide
Invoice gross-up calculation guide
Gross-up is useful when a payment processor deducts fees but you still need to receive a specific net amount. Instead of guessing how much extra to add, enter the percentage fee and fixed fee and let the calculator solve for the smallest gross charge that meets your target.
Formula
The starting equation is gross = (desired net + fixed fee) ÷ (1 − percentage rate). Earnquo then checks the result at currency precision and rounds upward only when necessary, so the calculated net does not fall one cent below your target.
Example
If you want to keep €1,000 and the fee is 3.4% plus €0.35, the calculated charge is €1,035.56. After the estimated €35.56 fee, the remaining amount is exactly €1,000.00.
Frequently asked questions
Can I use this for any payment provider?
Yes, when the provider fee can be represented as a percentage plus a fixed amount. Enter the fee terms yourself. More complex tiered, capped or currency-dependent pricing may require a provider-specific calculator.
Is gross-up the same as adding the fee percentage?
Not exactly. Simply adding the percentage to the desired net can leave you short because the processor also charges its percentage on the extra amount. Gross-up solves the equation in reverse instead.