Méthodologie
How we calculate tips
Our methodology for the Pourboire calculator: the formula, step-by-step calculation, authoritative sources, and limitations. Reviewed quarterly.
Formule
tip = bill × (tip% / 100)
Étape par étape
- 1
Determine the pre-tip bill amount.
- 2
Decide on the tip percentage. Common: 15% (standard), 18% (good service), 20% (excellent), 25%+ (exceptional).
- 3
Convert the tip percentage to a decimal: 18% → 0.18.
- 4
Multiply the bill by the decimal: $50 × 0.18 = $9.00 tip.
- 5
Add the tip to the bill to get the total: $50 + $9 = $59.
- 6
To calculate the tip from a final amount (tax already included), use the same formula on the pre-tax subtotal.
Sources autorisées
Every claim on this page is backed by an authoritative source.
Hypothèses
What we take to be true when applying this formula.
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Tip is calculated on the pre-tax subtotal (not the final amount).
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Standard US tipping rates apply. Customs vary by country (Japan: no tips; much of Europe: service included).
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The bill is the gross amount before any discount or coupon.
Limites
What this method does NOT capture.
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Tipping norms differ by country, establishment, and service type. This calculator uses US norms.
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For large groups (6+), some restaurants auto-add 18–20% gratuity.
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Sales tax is sometimes included in the "bill" depending on the establishment. The result is the same.
Dernière révision: 2026-06-15 • Reviewed by: CalcxApp editorial team