Tip Calculator

Receipt: {{ resultsReady ? moneyCents(computation.values.receipt_total_cents) : '—' }} Per person: {{ resultsReady ? shareRangeDisplay : '—' }} Check: {{ resultsReady ? reviewLabel : '—' }}

Bill subtotal:

The pre-tax receipt amount.

Tax rate:

Use 0 when the receipt has no separate tax.

Tip method:

Percentage Fixed amount

Tip rate:

Applied to the selected tip basis.

Tip amount:

The total tip for the receipt, not per person.

Percentage tip basis:

Fixed-tip mode compares its effective rate with the pre-tax subtotal.

People:

Use an itemized splitter when diners owe different amounts.

people

Per-person settlement:

Any round-up difference appears in Receipt check.

Service charge:

The neutral default is 0.

Display currency:

USD is the default display convention.

Line item	Amount	Calculation	Decision note	Copy
{{ row.label }}	{{ row.amount }}	{{ row.calculation }}	{{ row.note }}

Person	Pays	Tip share	Settlement note	Copy
{{ row.person }}	{{ row.pays }}	{{ row.tipShare }}	{{ row.note }}

Check	Status	Evidence	Next action	Copy
{{ row.check }}	{{ row.status }}	{{ row.evidence }}	{{ row.action }}

The chart renderer is unavailable. The same values remain available in Receipt breakdown.

The percentage printed on a payment screen is not enough to determine a tip. The result also depends on which receipt amount receives that percentage, whether a compulsory service charge is already present, and how the final total is divided among the people paying.

A subtotal is the pre-tax price. Tax is a separate charge calculated from that subtotal. A service charge is required once it appears on the bill, while a tip is an amount the customer chooses. In the United States, the IRS also treats mandatory service charges differently from voluntary tips for tax purposes; terminology and local rules can differ elsewhere.

Receipt components that affect a tip calculation
Receipt amount	Role in the calculation	Point to check
Subtotal	Pre-tax price and the usual percentage-tip base	Confirm discounts and excluded items are already reflected
Tax	Added to the amount due; optionally included in the tip base	Use the rate and amount shown on the receipt
Service charge	Compulsory amount included in the receipt total	Read the receipt before adding another gratuity
Tip	Percentage of a chosen base or one fixed amount	Percentage presets are suggestions, not universal rules

Pre-tax and after-tax tipping can produce different answers from the same rate. Including a service charge in the percentage base increases the amount again. A fixed tip avoids that base decision, but its effective rate still needs the pre-tax subtotal for a meaningful comparison.

Splitting introduces a second rounding problem. An exact equal split can assign leftover cents to the first few shares so every payment still sums to the receipt. Rounding every share upward to 0.50 or 1.00 makes cash collection simpler, but the group may collect more than is owed.

A shared total assumes everyone owes an equal portion of the complete receipt. It does not account for different meals, alcohol, discounts, or separate service choices. Use an itemized split when those differences matter.

How to Use This Tool:

Rebuild the receipt first, then choose the gratuity and settlement rules.

Enter the Bill subtotal and Tax rate. Add any compulsory Service charge separately so it is visible in the final check.
Choose Percentage and set the tip basis, or choose Fixed amount and enter the total tip for the whole receipt.
Enter the number of People. Keep Exact cents when the collected shares must equal the receipt, or select an upward 0.50 or 1.00 settlement step for cash-friendly shares.
Review Receipt breakdown for the amount due and Payment shares for each equal payment.
Check Receipt check before collecting money. A service-charge warning, unusually high rate, or rounding cushion needs a deliberate decision.

Interpreting Results:

Tip is the voluntary amount calculated or entered for the receipt. Receipt total adds subtotal, tax, service charge, and tip. Collected total can be higher only when each person's share is rounded upward.

An effective tip above 35% or a tax rate above 35% receives a review warning, not an error. Confirm that the values were entered as whole percentages. When Settlement rounding says Collects extra, assign or return the stated cushion rather than treating it as part of the original receipt.

Technical Details:

Money is converted to integer minor units before the receipt is assembled. Percentage-derived tax and tip amounts are rounded to the nearest minor unit, so later additions and exact-cent allocation do not rely on floating-point currency strings.

Formula Core

Let S be the subtotal in minor units, r_tax the tax percentage, B the selected percentage-tip base, r_tip the tip percentage, and C the service charge:

\begin{matrix} Tax = round (S \times \frac{r_{tax}}{100}) \\ Tip = round (B \times \frac{r_{tip}}{100}) \\ Total = S + Tax + C + Tip \end{matrix}

The percentage base is one of subtotal, subtotal plus tax, or subtotal plus tax and service charge. Fixed-tip mode replaces the percentage equation with the entered fixed amount and reports its effective percentage against the subtotal.

With a 48.75 subtotal, 8.25% tax, an 18% pre-tax tip, and two people, tax rounds to 4.02 and tip rounds to 8.78. The 61.55 receipt divides into 30.78 and 30.77 so the two shares remain exact.

Rule Core

Exact settlement divides the integer total by the number of people. Each person first receives the whole-unit quotient; one remaining minor unit is added to each earliest share until the remainder is exhausted. Upward settlement instead applies a ceiling to every person's unrounded average:

share = k \times ⌈ \frac{\frac{Total}{people}}{k} ⌉

Here, k is 50 minor units for 0.50 rounding or 100 minor units for 1.00 rounding. The rounding cushion is the collected total minus the exact receipt total and is always shown separately.

Tip calculator input limits and semantics
Input	Accepted range	Meaning
Subtotal and charges	0 to 1,000,000	Entered in the displayed currency
Tax rate	0% to 60%	Applied to subtotal
Tip rate	0% to 100%	Applied to the selected base
People	1 to 50	Whole-number equal shares only
Currency	Eight display choices	Changes symbols and labels; no exchange-rate conversion occurs

References:

Tip recordkeeping and reporting, Internal Revenue Service.