Invoice Calculators
Quick math for your invoices: late fees, VAT/GST, due dates and invoice numbers.
Late Fee Calculator
Late fees and interest on overdue invoices: an annual rate (simple or compounded daily), % per month, % per day, a one-time % or a flat fee, with legal default rates for 50 states + DC.
CalculatorVAT / GST Calculator
Add VAT to a net price or extract VAT from gross, with country presets verified against official sources.
CalculatorReverse VAT Calculator
Take VAT out of a VAT-inclusive (gross) price: the net price and the VAT it contains, for any rate.
CalculatorReverse Charge VAT Calculator
VAT to self-account, VAT to deduct and your net cost under the reverse charge, with EU and UK invoice wording.
CalculatorUK VAT Deadline Calculator
VAT return and payment due dates for the standard scheme, Annual Accounting and payments on account, with Direct Debit, CHAPS and Bacs timing.
CalculatorInvoice Due Date Calculator
Invoice date + payment term = due date and weekday: Net terms, EOM (both methods), prox, 2/10 Net 30, and days between two dates.
CalculatorBilling Cycle Calculator
Every billing date of a 7, 14, 28 or 30-day, monthly, quarterly or yearly cycle, with each invoice's due date.
CalculatorInvoice Calculator
Add line items, a discount, tax, shipping and a deposit; see the formula with your numbers.
CalculatorInvoice Number Generator
The next sequential invoice number or a numbered list, in formats like INV-2026-001.
GeneratorRandom Invoice Number Generator
Random, non-sequential invoice-style IDs (4–16 characters, up to 100 at a time), generated in your browser. For VAT/GST invoices use a sequential series.
GeneratorPO Number Generator
Next PO number or a numbered batch for your PO log, with an optional department or project code.
Letter toolDemand Letter Generator
A formal demand for payment with the interest computed and, if no rate was agreed, your state's statute cited.
CalculatorEarly Payment Discount
What 2/10 Net 30 is really worth, annualized — for the buyer and the seller.
CalculatorDSO Calculator
Days Sales Outstanding from your receivables and credit sales — and what a faster cycle frees up.
CalculatorInvoice Aging Calculator
Paste your open invoices, get an aging report by bucket (current, 1–30, 31–60, 61–90, 90+).
ConverterAmount to Words
Invoice totals written out in words — international (million/billion) or Indian (lakh/crore) numbering.
About these calculators
The calculators provided on MyInvoiceTemplate are for general business purposes and convenience only. They do not constitute professional accounting, tax, or legal advice. Statutory interest rates and VAT/GST rules vary by contract and jurisdiction and change over time, so please confirm the applicable figures with a certified accountant before relying on a result.