Business calculator
Editor
Estimate practical flat late fees, monthly finance charges, or annual interest on overdue invoices in the same calm Toolistri business-calculator layout.
Keep the overdue balance, overdue timing, and fee method visible immediately so the calculator stays quick to use.
Invoice amount
Use the overdue invoice amount or unpaid balance the late fee applies to.
Overdue timing
This first version uses days overdue only so the estimate stays fast, simple, and easy to scan.
Late fee method
Choose the fee method used in your payment terms or the invoice scenario you want to compare.
Fee amount or rate
Enter the setting used by the selected late-fee method. The other method settings stay in the background for the comparison card.
This calculator estimates late-fee math only. It does not tell you whether a fee is legal, enforceable, or correctly disclosed.
Use a grace period or fee cap when you want the estimate to match your payment terms more closely.
Results
Late fee amount
$54.00
Total amount due
$2,454.00
Overdue days
45
Fee-eligible days
45
Original invoice amount
$2,400.00
Overdue days
45
Late fee method
Monthly percentage
Configured fee setting
1.5%
Grace period
None
Fee-eligible days
45
Effective late fee %
2.25%
Total amount due
$2,454.00
| Measure | Value |
|---|---|
| Original invoice amount | $2,400.00 |
| Overdue days | 45 |
| Grace period | No grace period |
| Fee-eligible overdue days | 45 |
| Late fee method | Monthly percentage |
| Monthly late rate | 1.5% |
| Time basis used | Daily proration from a 30-day month |
| Raw late fee before cap | $54.00 |
| Calculated late fee | $54.00 |
| Effective late fee % | 2.25% |
| Total amount due | $2,454.00 |
Flat fee
$35.00
Monthly percentage
$54.00
Annual interest
$53.26
Businesses should disclose late fees and payment terms clearly in invoices or contracts whenever possible. Local law, contract wording, notice requirements, and industry rules can all affect whether a fee is enforceable, even when the math is straightforward.
How it works
This calculator provides planning estimates only. Contract terms, local law, industry rules, and statutory commercial late-payment standards can affect whether a late fee is enforceable. Confirm your invoice terms and applicable law before charging a fee or finance charge.
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