How to Calculate a Tip
The fastest way to calculate a 20% tip is to move the decimal one place left (10%) and then double it. A $47 bill: 10% = $4.70, doubled = $9.40 for a 20% tip. Total with tip = $56.40.
For 15%, take 10% and add half: $4.70 + $2.35 = $7.05. For 25% (exceptional service), take 10%, multiply by 2.5: $4.70 × 2.5 = $11.75.
Should you tip on the pre-tax or post-tax amount? The official etiquette is to tip on the pre-tax subtotal — the tax is collected by the government, not the server. That said, in practice, many people tip on the total because it's simpler and the difference is small. On a $50 pre-tax bill with 8% sales tax ($54 total), tipping 20% pre-tax = $10 vs. post-tax = $10.80. Most servers won't mind either way.
Standard Tipping Rates by Service Type
Tipping norms vary significantly by industry and have shifted upward over the past decade. Here's the current consensus across service types:
Restaurant sit-down: 18–22% for standard service, 25%+ for exceptional. Quick service/counter: 10–15% if a tip jar or touchscreen prompt is present — you're not obligated. Food delivery: 15–20% of order total or $3–5 minimum (drivers often pay for gas and wear on their vehicles). Bartenders: $1–2 per drink or 15–20% of tab. Hotel housekeeping: $3–5 per night (often overlooked but important). Taxi/rideshare: 15–20%. Hair salons: 20%. Movers: $20–50 per mover depending on complexity.
The rise of digital payment systems and tip prompts has introduced 'tip creep' — screens now commonly suggest 20%, 25%, and 30% as default options. There's no obligation to follow these suggestions, particularly for counter service or takeout where tipping was not traditionally expected.