Toolkit Shelf

Business Calculators

Invoice Generator

Use this invoice generator to calculate line item totals, subtotal, discount, tax, and balance due for a simple client invoice.

Reviewed May 25, 2026EstimateFormula shown

Live generator

Invoice total

Balance due$2,160.00

Invoice estimate for Client.

Subtotal$2,000.00

Line items before discounts and tax.

Discount$0.00

0.0% discount before tax.

Tax$160.00

8.0% on the discounted subtotal.

Invoice line items
ItemQuantityRateTotal
Consulting10$125.00$1,250.00
Project work1$750.00$750.00

Formula

Invoice total formula

Balance due = subtotal - discount + tax; subtotal = sum(quantity x rate); tax = (subtotal - discount) x tax rate

This generator calculates totals. It does not replace accounting, tax, or legal invoice requirements in your jurisdiction.

How to use

Steps

  1. Enter the client name and two line items.
  2. Add quantity and rate for each line item.
  3. Enter any discount percentage before tax.
  4. Enter the tax rate and review the balance due.

Example

Sample calculation

Consulting10 x $125
Project work1 x $750
Tax8%
Balance due$2,160

Calculator use

Best for

  • Quick invoice total from client, line items and quantity.
  • Pricing, runway, cash flow, or work assumptions before an operating decision.
  • Base, conservative, and optimistic cases with visible inputs.
  • Calculator math that can be shared with a teammate, client, or advisor.

Before relying on it

Check first

  • Entering client, line items and quantity from different time periods or scenarios.
  • Mixing cash and accounting profit, or monthly recurring items and one-time items.
  • Leaving out taxes, payment fees, refunds, churn, seasonality, or delayed collections.
  • Using one optimistic scenario without checking a conservative scenario too.

Benchmarks

How to read the result

The calculator is a decision aid, not a fixed rule. Use the output to compare scenarios and document your assumptions.

Net 0 - 7Fast payment

Often used for small jobs, deposits, or clients with simple approval steps.

Net 15 - 30Common terms

A common range for freelancers and small businesses when payment approval takes time.

Net 45+Long terms

Can strain cash flow, so late fees, deposits, or milestone billing may matter more.

Calculator accuracy

Methodology and assumptions

The formula, inputs, example, and limitations are shown so the result is checkable, not just a number in a box.

Formula

Balance due = subtotal - discount + tax; subtotal = sum(quantity x rate); tax = (subtotal - discount) x tax rate

Inputs used

Client, Line items, Quantity, Rate, Discount, Tax

Limitations

Results are estimates for quick planning and should be checked before important financial, legal, tax, health, or business decisions.

Last reviewed

May 25, 2026

Cite this page

Toolkit Shelf. Invoice Generator. Retrieved May 25, 2026, from https://toolkitshelf.com/tools/invoice-generator

FAQ

Common questions

What should an invoice include?

A basic invoice usually includes seller and client details, invoice number, date, line items, subtotal, taxes, total, due date, and payment instructions.

Is tax calculated before or after discount?

This generator applies discount first, then calculates tax on the discounted subtotal. Rules can vary by location and invoice type.

Can I use this as my official invoice?

Use it to calculate the invoice total and line items. Check local requirements before sending official business or tax documents.