Build invoices from time, expenses, taxes, and credits. Review subtotals, taxes, discounts, and credits instantly. Present precise client billing summaries for matters and invoices.
Enter time, pricing, credits, and invoice adjustments. The result appears above this form after submission.
This waterfall chart shows how charges, discounts, taxes, and credits shape the final invoice amount.
The calculator rounds time to your chosen billing increment, applies rate adjustments, then subtracts credits after taxes.
Raw Minutes = (Hours Worked × 60) + Extra Minutes
Rounded Minutes = CEILING(Raw Minutes ÷ Billing Increment) × Billing Increment
Rounded Billable Hours = MAX(Minimum Billable Hours, Rounded Minutes ÷ 60)
Labor Fee = Rounded Billable Hours × Hourly Rate × Complexity Multiplier
Pre-Discount Subtotal = Labor Fee + Flat Fee + Expenses + Late Fee
Discount Amount = Percentage or Fixed Reduction, capped at the subtotal
Taxable Base = Pre-Discount Subtotal − Discount Amount
Gross Invoice = Taxable Base + (Taxable Base × Tax Rate)
Final Balance Due = Gross Invoice − Retainer Credit − Trust Credit
1. Enter the client name and matter reference for a cleaner exported summary.
2. Add hourly rate, worked hours, and leftover minutes from your time entry.
3. Choose the billing increment, such as 6, 10, or 15 minutes.
4. Set a minimum billable time if your engagement letter requires it.
5. Add complexity multiplier when premium work justifies a higher billing factor.
6. Include flat fees, filing costs, courier expenses, or any late charges.
7. Apply a discount by percentage or fixed value, then enter tax rate.
8. Deduct retainer and trust credits to see the actual remaining balance.
9. Submit the form and review the result block above the calculator.
10. Use the CSV and PDF buttons to export the billing summary.
| Scenario | Rate | Rounded Hours | Expenses | Discount | Tax | Credits | Final Balance |
|---|---|---|---|---|---|---|---|
| Contract review with filing costs | $325.00 | 5.70 | $85.00 | 5% | 8.25% | $300.00 | $1,948.97 |
| Drafting addendum with flat fee | $275.00 | 3.20 | $40.00 | $50.00 | 7.00% | $200.00 | $804.26 |
| Lease markup and trust credit | $350.00 | 2.50 | $25.00 | 0% | 6.50% | $500.00 | $430.63 |
These are illustrative samples for reviewing layout and billing behavior.
Law firms often bill in fixed increments like six or fifteen minutes. Upward rounding converts recorded work into standard billing units that match engagement terms and invoicing policies.
Some matters require a minimum charge for calls, reviews, or quick drafting tasks. This field keeps the invoice aligned with those minimum billing commitments.
Use it when a matter justifies a premium factor because of urgency, specialist knowledge, unusual document risk, or negotiated pricing terms with the client.
A percentage discount scales with the subtotal, while a fixed discount subtracts one exact amount. The calculator caps either discount so it never exceeds the subtotal.
That depends on your jurisdiction and invoice rules. This calculator applies tax to the taxable base you create, so verify local treatment before relying on the output.
They are client funds already held and available to offset the invoice. Enter them to reduce the final balance and reflect funds previously collected.
Yes. Add a flat fee or document charge, then include time, expenses, discounts, and credits as needed for a mixed billing arrangement.
A negative balance means credits exceed the invoice total. In practice, that often indicates a remaining client credit or trust balance after the bill is covered.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.