Hourly Invoice

Total due —

Billable hours: —
Subtotal: —
Tax: —
Line items: —
Invoice text to copy: —

List each task with its time at the end of the line, enter your hourly rate and any sales tax, and the invoice totals itself. For example, 2.5 hours of auditing plus 1 hour of edits at 80 per hour gives a 280 subtotal, 28 in tax at 10%, and 308 due.

About this tool

Freelancers, consultants, tutors and contractors who bill by the hour usually keep time in a notes file or a timer export, then retype it into an invoice. Here you paste those lines as they are: the time at the end of each line can be decimal hours, h:mm, 2h 15m or plain minutes. Every line becomes an itemised row with its hours and amount, and you get billable hours, subtotal, tax and the total due, plus a plain invoice text block to copy into an email or your own template. Each line can be rounded up to 6-minute or 15-minute blocks, which is how many contracts define billable time. It does not know the tax rules for your location or whether your service is taxable at all, so the tax percentage is whatever you enter.

How to use it

Paste or open your time log
Put one task per line with its time last, or open a .txt or .csv export from your timer.
Set the rate and rounding
Enter the hourly rate and choose exact time, 6-minute or 15-minute blocks to match your agreement.
Add tax if it applies
Enter the sales tax or VAT percentage your jurisdiction charges on the service, or leave it at 0.
Fill the header and copy
Add the currency code, invoice number and client, then copy the invoice text from the results.

Examples

3.5 hours at 80 with 10% tax

Work lines: Site audit, 2.5 Copy edits 1:00
Hourly rate: 80
Sales tax / VAT: 10
Round each line up to: Exact time
Currency code: USD

Result Total due: 308.00
Billable hours: 3.5
Subtotal: 280.00
Tax: 28.00
Line items: 2
Invoice text to copy: INVOICE
1. Site audit — 2.5 h × 80 = USD 200.00
2. Copy edits — 1 h × 80 = USD 80.00
Subtotal: USD 280.00
Tax (10%): USD 28.00
Total due: USD 308.00

Billable hours = 2.5 + 1 = 3.5 h
Subtotal = sum of hours × 80 per line = 280.00
Tax = 280.00 × 10% = 28.00
Total due = 280.00 + 28.00 = 308.00

A half-day audit and an hour of edits come to 280 before tax and 308 once 10% is added.

Rounding up to 15-minute blocks

Work lines: Client call 20m Bug fix 1h 10m
Hourly rate: 100
Round each line up to: 15 minutes (0.25 h)
Currency code: USD

Result Total due: 175.00
Billable hours: 1.75
Subtotal: 175.00
Tax: 0.00
Line items: 2
Invoice text to copy: INVOICE
1. Client call — 0.5 h × 100 = USD 50.00
2. Bug fix — 1.25 h × 100 = USD 125.00
Subtotal: USD 175.00
Total due: USD 175.00

Billable hours = 0.5 + 1.25 = 1.75 h (each line rounded up to 0.25 h)
Subtotal = sum of hours × 100 per line = 175.00
Tax = 175.00 × 0% = 0.00
Total due = 175.00 + 0.00 = 175.00

A 20-minute call bills as half an hour and a 70-minute fix as 1.25 hours, so 1.75 hours at 100 is 175.

How it is calculated

Total = Σ (hᵢ × R) × (1 + T ÷ 100), with hᵢ = ⌈tᵢ ÷ b⌉ × b when rounding is on

tᵢ: time recorded on line i, in hours
b: billing increment: 0.1 h or 0.25 h
hᵢ: billable hours on line i
R: hourly rate
T: sales tax or VAT percentage

Each line's time is read from the end of the line and converted to hours (1:30 and 1h 30m are both 1.5). If a billing increment is chosen, each line is rounded up separately, so a 7-minute task bills as 0.1 h or 0.25 h. Line amounts are rounded to cents, added into the subtotal, and tax is applied once to that subtotal.

Sources

Invoicing and taking payment from customers — GOV.UK
Recordkeeping for small businesses — Internal Revenue Service

When not to use it

Fixed-fee or milestone work is better billed as a lump sum than as hours.
Different rates for different tasks need separate invoices or a line-item tool with per-row rates.
A VAT invoice in some countries needs your tax registration number and supply date, which this text does not add.

Common mistakes

Writing 1.30 for an hour and a half reads as 1.3 hours; use 1:30 or 1.5.
Putting the time in the middle of a line means it is not read; the time must come last.
Rounding the weekly total instead of each line gives a different figure from per-task rounding.
Charging tax on a service that is exempt where you work inflates the client's bill.

Frequently asked questions

Which time formats can I write at the end of a line?

Decimal hours such as 2.5, clock style such as 2:30, hours and minutes such as 2h 30m, or minutes alone such as 150m. All four give 2.5 hours. A comma, dash or space between the task and the time is fine.

How does 6-minute rounding work?

A tenth of an hour is 6 minutes, so each line is rounded up to the next 0.1 h. A 7-minute call becomes 0.2 h and a 30-minute task stays 0.5 h. Rounding happens per line, so many short tasks add more than one long one.

What happens to lines without a time?

They are left off the invoice and a warning tells you how many were skipped, so headings or notes in your time log do not break the total. Check the warning count before you send the invoice.

Is tax worked out per line or on the total?

Once, on the subtotal. Each line amount is rounded to two decimals first, then the tax percentage is applied to their sum, which is how most single-rate invoices are calculated.

What should an invoice include besides the amounts?

GOV.UK lists a unique invoice number, your business name and address, the client's name and address, the date of supply and invoice date, a clear description of what you are charging for, and the amount due. VAT-registered businesses need extra details such as the VAT number.

Can I bill in euros or pounds?

Yes. Type any currency code such as EUR or GBP; it is added to each amount in the invoice text. No conversion happens, so the rate should already be in that currency.

How long should I keep copies of invoices?

The IRS guidance on recordkeeping says to keep records that support income for as long as they may be needed for tax purposes, often at least three years. Save the copied invoice text together with your original time log.