How much should I tip at a restaurant in the US?

Standard tipping at US full-service restaurants is 18% to 20% of the pre-tax bill for adequate service, 25% or more for excellent service, and 15% or slightly below for service that genuinely fell short. Counter service, fast-casual, and takeout typically see 10% to 15% or no tip, depending on the establishment. Bartenders traditionally receive $1 to $2 per drink or 15% to 20% of the bar tab.

Do I tip on the pre-tax or post-tax total?

The widely accepted standard in the United States is to tip on the pre-tax subtotal, not on the tax-inclusive total. Tipping on the post-tax amount effectively increases your tip percentage beyond what you intend. This calculator uses the bill amount you enter as the tipping base, so enter your pre-tax subtotal for a tip that follows the standard US convention.

How do I split a bill unevenly when people ordered different amounts?

Use the Proportional Split mode in this calculator. Enter each person's individual bill amount and the tip percentage. The calculator divides the total tip proportionally based on each person's share of the subtotal. For example, if one person ordered $60 worth of food and another $40, the first person pays 60% of the tip and the second pays 40%, so heavy orderers pay more of the tip than light ones.

What is the tipping etiquette for delivery drivers in the US?

Delivery drivers in the US typically receive 15% to 20% of the food total, with a minimum of $3 to $5 for small orders, especially in bad weather or difficult conditions. Third-party app delivery drivers (DoorDash, Uber Eats, Grubhub) often rely on tips as a primary part of their income rather than a supplement, so the higher end of the range is appropriate in most cases. Some delivery platforms default to suggesting a set dollar amount; use this calculator to verify what percentage that represents before accepting the suggested default.

How do I calculate a 20% tip quickly in my head?

Move the decimal one place left to find 10%, then double it for 20%. On a $65 bill: 10% is $6.50, doubled is $13.00 for a 20% tip. For 15%, find 10% and add half: $6.50 + $3.25 = $9.75. For 18%, find 10% ($6.50) plus 8% (roughly $5.20 total, or $6.50 x 0.8) = $11.70. Use this calculator for precision, but the 10% shortcut helps you sanity-check any suggested tip before you sign the receipt.

Should I tip at a coffee shop or counter service?

Tipping at coffee shops and counter service has become common due to tablet point-of-sale systems that present preset tip prompts at checkout. There is no social obligation to tip at pure counter service where no one brings food to your table, but a $1 tip per drink or 15% is a reasonable gesture for a regular order. For complex or customized orders requiring significant preparation time, a 15% to 20% tip is considerate. The decision is entirely at your discretion.

Is it rude not to tip in the United States?

In full-service restaurants, not tipping is considered rude and causes genuine financial hardship to servers, who earn a federal tipped minimum wage of $2.13 per hour in most states and rely on tips to reach a livable income. In services like hair salons, taxi rides, hotel housekeeping, and food delivery, not tipping is considered poor etiquette even if it is not mandatory. In counter service, fast food, and retail, tipping is optional and omitting it carries no social penalty.

What is the tipped minimum wage in the US?

The federal tipped minimum wage is $2.13 per hour under the Fair Labor Standards Act. Employers must make up the difference if tips do not bring a worker to the federal minimum wage of $7.25 per hour, but enforcement is imperfect. Many states have higher minimum wages for tipped workers, and some states (including California, Washington, and Minnesota) require tipped workers to receive the full state minimum wage before tips. Understanding this context explains why tipping at full-service restaurants in the US is a near-mandatory social expectation rather than a true optional courtesy.

How does the round-up feature in this calculator work?

When you check the Round Up Each Person's Share box, the calculator rounds each person's total bill up to the nearest whole dollar before displaying it. This simplifies cash payments and eliminates the awkwardness of splitting $13.27 per person. For example, if each person owes $13.27, the rounded amount becomes $14.00. The slight overpayment effectively becomes a small extra tip, which is appreciated by the server and makes settling the bill faster.

How do I tip at a hotel?

Hotel tipping conventions in the US: Bellhop or luggage handler: $2 to $5 per bag. Housekeeping: $3 to $5 per night, left daily (not just at checkout, since different staff may clean each day). Room service: 18% to 20% of the bill if not already included as a service charge; check the receipt before adding more. Concierge: $5 to $20 depending on the complexity of the service provided. Valet parking: $2 to $5 when the car is returned.

What is a service charge and is it the same as a tip?

A service charge is a mandatory fee added to the bill by the establishment, typically 18% to 22% at upscale restaurants or for large parties. It is not the same as a tip: it goes to the restaurant as revenue, and the restaurant then decides how much, if any, to distribute to the staff. In contrast, a tip paid directly to the server goes to the server. Always check your bill for an included service charge before adding a tip, or you may double-tip unintentionally. The line item will typically say Service Charge, Auto Gratuity, or something similar.

How do I handle tipping when a large party has a mandatory gratuity added?

Most US restaurants automatically add 18% to 20% gratuity for parties of 6 or more. This appears on your bill as Auto Gratuity or Mandatory Gratuity. You do not need to add an additional tip on top of this, though you can if service was exceptional. The mandatory gratuity should be clearly disclosed on the menu or by the server before you order. If you notice an automatic gratuity and service was poor, you can ask to speak with management, but in most cases the gratuity cannot be removed.

How should tips be split when sharing a Venmo or Zelle payment?

Use the Proportional Split mode to calculate each person's total including their fair share of the tip, then share the results via the WhatsApp button. Everyone pays the person who covered the bill their calculated total. The proportional mode accounts for different order sizes, so someone who ordered more pays a larger share of the tip. If everyone ordered similar amounts, the Equal Split mode is simpler and produces the same result as dividing the total bill by the number of people.

How accurate is this tip calculator?

This calculator uses Big.js for all arithmetic, which eliminates the floating-point errors that standard JavaScript can produce at certain decimal values. For example, dividing a $78.50 bill three ways without precision handling might produce $26.166666... rendered incorrectly. Big.js returns the mathematically correct result and rounds to the display precision only at the final output step. Results are accurate to the penny for any bill amount and any tip percentage.

What does the chart in the results show?

In Equal Split mode, a doughnut chart shows the breakdown of your total bill into the pre-tip subtotal and the tip amount, giving a visual sense of what fraction of your payment goes to the server. In Proportional Split mode, a bar chart shows each person's total owed, making it immediately visible who owes the most and who owes the least. Both charts update automatically with every calculation.

Can I tip with a credit card at US restaurants?

Yes, virtually all US restaurants accept tip additions on credit card receipts. You write in the tip amount on the paper slip or select it on a payment terminal screen, then the final total is charged to your card. Some restaurants settle the full amount including tip in a single authorization, while others charge the pre-tip total first and then add the tip as a separate adjustment within a day or two. If you are using a debit card, be aware that some banks hold an authorization for an estimated total including a default tip percentage before the final amount settles.

Is tipping legally required in the US?

No, tipping is not legally required in the United States. It is a deeply embedded social convention, particularly at full-service restaurants where servers' wages legally assume tip income. However, some establishments add mandatory service charges for large parties or at high-end venues, which are legally enforceable as part of the bill. Outside of those mandatory service charges, no law compels a customer to leave a tip, though failing to do so at full-service restaurants is widely considered poor etiquette and directly affects a worker who depends on tips.

How do I use the custom tip dollar amount mode?

Click the Custom button in the tip preset row. A dollar amount field appears where you enter the exact tip you want to leave in dollars, not as a percentage. The calculator then computes the effective tip percentage, the total bill, and all per-person amounts based on that fixed dollar tip. This mode is useful when you want to leave a specific amount regardless of the bill total, or when you want to verify what a specific dollar tip represents as a percentage.

🍴 Math and Unit Conversion

Tip Calculator and Bill Splitter: Equal Split, Proportional Split, and Round Up

Quick preset buttons for 15, 18, 20, and 25 percent. Split equally or by what each person ordered. Round up to clean dollar amounts. Full per-person breakdown with a PDF receipt and WhatsApp share.

Equal and Proportional Split Quick Tip Presets Round Up Mode Per-Person Table PDF Receipt WhatsApp Share

🍴

Tip Calculator and Bill Splitter

Tip Percentage

Custom Percentage

Tip Dollar Amount

Enter exact tip amount in dollars

Total Bill (before tip)

Enter the pre-tax subtotal from your receipt

Number of People

people

Round each person’s share up to the nearest whole dollar

Bill Results

$0.00 Total with Tip

$0.00 Total Tip

$0.00 Per Person Total

$0.00 Per Person Tip

Name	Their Bill	Tip Share	Total

How the Math Works

Tipping in America: What the Unwritten Rules Actually Say

If you have ever sat at a restaurant table staring at a credit card slip wondering whether 18 or 20 percent is right, or stood at a coffee shop counter watching a tablet screen cycle through 20, 25, and 30 percent suggestions, you already know the tipping landscape in the United States is both complicated and emotionally charged. No federal law requires tips. But American tipping culture developed alongside a wage system that legally assumes tip income, making a voluntary custom feel anything but optional for the people who depend on it.

Understanding why tipping works the way it does in the US makes it easier to apply the right amount in the right situation, rather than defaulting to whatever number the payment terminal presents or freezing at the table trying to do math after a long meal.

The Wage Structure That Makes Tips Matter

Under the federal Fair Labor Standards Act, employers may pay tipped workers a cash wage as low as $2.13 per hour, with the expectation that tips will bring total hourly earnings up to the federal minimum wage of $7.25. If they do not, the employer is legally required to make up the difference, but enforcement of this requirement is inconsistent. In practice, many servers in US states that use the federal tipped minimum wage earn most of their income from tips. A busy Friday dinner shift at a mid-scale restaurant can produce a good tip income; a slow Tuesday lunch at an understaffed diner may not.

Many states have enacted higher tipped minimum wages, and a handful, including California, Washington, Alaska, and Minnesota, require tipped workers to receive the full state minimum wage before any tips. In those states, tips truly are a supplement rather than a primary income source. But across most of the country, the tip you leave at a sit-down restaurant is not a bonus for excellent service but a core part of what the server earns for their work.

What the Standard Percentages Actually Mean

15%: The historical standard tip, once considered perfectly adequate for good service. Today it signals that service was below expectations, though not bad enough to leave nothing. Leaving 15% at a full-service restaurant in 2025 reads as mild dissatisfaction rather than strong approval.

18%: The current baseline for satisfactory service in most US markets. This is the percentage this calculator defaults to because it represents the widely accepted minimum for a dining experience where nothing went wrong.

20%: The informal standard for good service. Easy to calculate (double the first digit of a two-digit percentage of the bill), which has contributed to its widespread adoption as a simple target. Twenty percent at a moderately priced restaurant is never wrong.

25% and above: Reserved for outstanding service, special occasions, or situations where the server went meaningfully above the standard. At high-end restaurants where servers handle complex multi-course meals, large wine lists, and extensive tableside service, 25% is considered a strong but not extravagant tip.

18% Default US restaurant tip rate this calculator uses for new calculations

$2.13 Federal tipped minimum wage per hour in states that use the federal floor

20% Widely accepted informal standard for good sit-down restaurant service in the US

Where Tips Are Expected and Where They Are Optional

Full-service restaurants, bars, coffee shops, delivery drivers, rideshare drivers, hotel staff, hair salons, spas, tattoo artists, and valet parking all operate within tipping cultures, though the strength of that expectation varies. At a full-service restaurant, skipping the tip is considered rude and financially harmful. At a coffee shop counter, skipping the tip is a personal decision with no meaningful social consequence. Knowing the difference saves you from both over-tipping out of social pressure and under-tipping in situations where it genuinely matters to the worker.

How Does This Tip and Bill Splitter Calculator Work?

Most tip calculators online handle one scenario: you enter a bill amount, pick a percentage, and they show you the tip and total. This calculator handles the two additional scenarios that actually arise when you are out with a group.

Equal Split Mode

Select Equal Split (the default). Enter the bill subtotal, choose a tip percentage using the preset buttons or type a custom percentage, enter the number of people, and click Calculate. The calculator computes the total tip, the grand total, each person’s share of the tip, and each person’s total. Check the Round Up box to have each share rounded up to the nearest whole dollar, which simplifies cash payments and slightly increases the effective tip as a small bonus to the server.

Proportional Split Mode

Select Proportional Split. Use the number selector to choose how many people (up to 8) are splitting the bill. Enter each person’s name (optional) and their individual subtotal. Choose the tip percentage. Click Calculate. The calculator sums all individual amounts to get the group subtotal, then distributes the tip proportionally so heavier orderers pay a larger share of the tip. The per-person results appear in a table showing each person’s subtotal, their tip share, and their total owed. This is the mode to use when everyone did not order the same amount and equal splitting feels unfair.

Custom Tip Amount in Dollars

Click the Custom preset button. A dollar amount field appears. Enter the exact tip you want to leave. The calculator computes the effective percentage, the total, and all per-person figures. Use this when you have a specific amount in mind regardless of the bill size, or when you want to verify what a specific dollar tip represents as a percentage before signing the receipt.

The PDF Receipt and WhatsApp Share

After calculating, the Download PDF Receipt button generates a branded document with the full bill breakdown, including per-person amounts in proportional mode. The Share on WhatsApp button composes a message with each person’s total and a link to the calculator, ready to send in a group chat so everyone knows exactly what to Venmo or Zelle.

Three Real US Tipping and Bill-Splitting Scenarios

Example 1: Dinner for Four in Nashville, Tennessee

Nashville, TN: Equal Split, 4 People

Four friends finish dinner at a mid-scale Nashville restaurant. The pre-tax subtotal is $184.60. Service was good, so they agree on 20% tip.

Tip: $184.60 x 0.20 = $36.92

Total with tip: $184.60 + $36.92 = $221.52

Per person (equal): $221.52 / 4 = $55.38 each

They check the Round Up box. Each person’s share rounds to $56.00, making the effective tip $40 (21.7%). The extra $2.48 goes to the server. Everyone pays $56 cash or Venmos the person who paid.

Example 2: Work Lunch in New York City (Proportional Split)

Midtown Manhattan: Proportional Split, 3 People

Three colleagues grab lunch in Midtown. Maria ordered a $28 salad and beverage. James had a $42 steak sandwich with sides and a cocktail. Lisa had a $19 soup and water. They use proportional split at 18% tip.

Group subtotal: $28 + $42 + $19 = $89

Total tip (18%): $89 x 0.18 = $16.02

Maria (31.5% of bill): $28 + ($28/$89 x $16.02) = $28 + $5.04 = $33.04

James (47.2% of bill): $42 + ($42/$89 x $16.02) = $42 + $7.56 = $49.56

Lisa (21.3% of bill): $19 + ($19/$89 x $16.02) = $19 + $3.42 = $22.42

James does not protest paying more of the tip since he ordered substantially more. Using the WhatsApp share button, Lisa sends all three totals to their group chat instantly.

Example 3: Brunch in Austin with a Custom Tip Amount

Austin, TX: Custom Dollar Tip, 2 People

Two friends at a popular Austin brunch spot end up with a $67.00 subtotal. Their server was exceptional and went out of their way to accommodate a dietary restriction. They want to leave $20 in cash as a tip regardless of the percentage.

Custom tip: $20.00

Effective percentage: $20 / $67 x 100 = 29.9%

Total on card: $67.00 + $0 (tip paid cash) = $67.00 charged, $20 left on the table

They enter $67 as the bill and $20 as the custom tip amount in the dollar tip mode to confirm the effective percentage before deciding whether to increase or keep it. The calculator confirms they are tipping just under 30%, which matches their intention to tip generously.

Expert Tips: Getting the Split Right Without Awkward Conversations

Tip 1: Agree on the Split Method Before the Check Arrives

The most uncomfortable bill-splitting moments happen when the check arrives and no one has agreed on a method. A quick “should we split this equally or by what we ordered?” at the start of the meal takes three seconds and prevents a long, awkward calculation session while the server waits. For groups with widely varying order sizes, the proportional mode produces a fairer result and is worth the thirty seconds it takes to enter each person’s amount. For groups where everyone had roughly similar meals, equal split is faster and avoids any appearance of nickel-and-diming over small differences.

Tip 2: Always Check Your Receipt for Automatic Gratuity Before Adding More

US restaurants commonly add a mandatory gratuity of 18% to 20% for parties of 6 or more, large event bookings, or certain high-end establishments as standard policy. This charge appears as Auto Gratuity, Mandatory Gratuity, or Service Charge on your itemized receipt, often at the bottom below the subtotal. If you add a tip on top without noticing, you are double-tipping. The calculator is most useful before you fill out the credit card slip: enter your subtotal, calculate 18% or 20%, and compare to what the receipt already shows. If the receipt total already reflects an added gratuity, you do not need to add another one.

Tip 3: Use the WhatsApp Share to Settle Group Tabs Instantly

One of the most common post-dinner friction points is settling who owes what when one person puts the whole bill on a card and everyone else needs to repay. Rather than doing individual math in the parking lot, calculate the proportional or equal split in this tool, then hit Share on WhatsApp. The share message includes each person’s full name (as entered) and their total owed, plus the link to the calculator for anyone who wants to verify the numbers themselves. This approach eliminates misunderstandings, cuts down on the time it takes to collect payment, and gives everyone a clear record to reference when sending their Venmo or Zelle payment later.

Frequently Asked Questions About Tipping in the US

Standard US restaurant tipping is 18% for satisfactory service, 20% for good service, and 25% or more for outstanding service. Fifteen percent signals mild dissatisfaction. For bar service, $1 to $2 per drink or 15% to 20% of the tab is standard. Leave this calculator defaulted at 18% and adjust up or down based on your experience.

The standard in the US is to tip on the pre-tax subtotal, not the tax-inclusive total. Tipping on the post-tax amount inflates your effective tip percentage beyond your intent. Enter your pre-tax subtotal in this calculator to follow the standard US convention. The difference is most noticeable in high-tax cities like Chicago or Seattle where sales tax can exceed 10%.

Proportional splitting means each person pays their own food total plus a share of the tip that corresponds to their fraction of the group’s bill. If one person spent twice as much as another, they pay roughly twice the tip. Use it when order sizes vary significantly enough that equal splitting feels unfair. For groups where everyone had similar meals, equal split is simpler and reaches nearly the same result.

Move the decimal one place left to find 10%, then double it for 20%. On a $85 bill: 10% is $8.50, doubled is $17.00 for a 20% tip. Total is $85 + $17 = $102. For 18%, find 10% + 8%: 10% is $8.50, 8% is $8.50 x 0.8 = $6.80, total tip is $15.30. Use this calculator for accuracy, especially when splitting between multiple people.

The federal tipped minimum wage is $2.13 per hour. Employers must make up the difference if tips do not bring a worker to the $7.25 federal minimum wage. Many states have higher minimums; California, Washington, Alaska, and Minnesota require tipped workers to receive the full state minimum wage before tips. This wage structure is why tipping at full-service restaurants is a near-mandatory social expectation rather than a true optional gesture.

At counter service and quick-service coffee shops, tipping is optional with no meaningful social obligation. A $1 tip per drink or 10% to 15% for complex orders is a reasonable gesture if you are a regular or the barista put extra effort into your order. The tablet tip prompts you see at counter service are a business choice by the establishment; you are not obligated to select any of the preset percentages.

A service charge is a mandatory fee added by the establishment, typically 18% to 22% for large parties or at upscale venues. It goes to the restaurant as revenue, not necessarily to the server. A tip is a voluntary payment that typically goes directly to the staff. Always check your receipt for an included service charge before adding a tip, or you may end up double-tipping. The line will read Auto Gratuity, Mandatory Gratuity, or Service Charge.

Food delivery drivers in the US typically receive 15% to 20% of the food total, with a minimum of $3 to $5 for small orders. In bad weather, for long distances, or for large orders, $5 to $10 minimum is appropriate. Third-party app drivers on DoorDash, Uber Eats, and Grubhub often rely on tips as a core part of their income. The tip you set in the app is what the driver receives, and lowering it after delivery is considered particularly poor etiquette.

Checking Round Up each person’s share rounds each person’s total up to the nearest whole dollar before displaying it. If someone owes $14.37, they pay $15.00. The extra $0.63 effectively becomes a small additional tip. This makes cash payment simpler and eliminates the need to break small bills or make change. The round-up applies after all tip math is complete, so the rounded amount is what each person pays, not an input to further calculations.

Hotel housekeeping in the US is typically tipped $3 to $5 per night. Leave the tip daily rather than just at checkout, since different staff may clean your room each day. Use a labeled envelope or a note specifying it is for housekeeping so the right person receives it. At luxury hotels where room rates and service standards are higher, $5 to $10 per night is more appropriate. This is one of the most frequently skipped tips in American hotels and one that genuinely matters to the workers involved.

No. Tipping is a social convention, not a legal requirement. Mandatory service charges added by the establishment are a legally enforceable part of the bill, but a voluntary tip for any service is entirely your decision. That said, at full-service restaurants the wage system assumes tip income, so omitting a tip entirely creates real financial harm to the server and violates a widely held social norm.

Calculate the split using equal or proportional mode, then hit the Share on WhatsApp button. The share message includes each person’s name and total owed, plus a link to this calculator for verification. Everyone can use those totals to send payment to whoever covered the bill. In proportional mode, names you enter in the person fields appear in the WhatsApp message, making it immediately clear who owes what.

Fifteen percent to 20% is standard for Uber and Lyft rides. For exceptional service (great conversation, helpful route suggestions, extra-clean vehicle, carrying heavy luggage), 20% to 25% is appropriate. For very short rides under $5, a minimum of $1 to $2 is courteous. Rideshare drivers do not receive the full fare; a significant portion goes to the platform, making tips a meaningful supplement. Both Uber and Lyft allow in-app tipping after your ride is complete.

This calculator uses Big.js for all arithmetic. Big.js is a precision decimal library that eliminates the floating-point errors that standard JavaScript produces at certain decimal values. Results are accurate to the penny for any bill amount, tip percentage, and number of people. The proportional split calculates each person’s exact share using division to eight decimal places before rounding to the display precision, so the displayed totals add up correctly.

In Equal Split mode, a doughnut chart shows the split between the bill subtotal and the tip amount, giving a visual sense of the tip fraction. In Proportional Split mode, a bar chart shows each person’s total owed, making it immediately visible how the bill is distributed across the group. Both charts update instantly with every calculation and use the same color scheme across chart and table for easy cross-reference.

The PDF includes a branded header, the bill subtotal, tip percentage, tip amount, total with tip, and the split mode used. In equal split mode it also shows the per-person tip and per-person total. In proportional mode it includes the full per-person breakdown table with each person’s name, their subtotal, their tip share, and their total owed. The PDF is useful as a record of the calculation, for expense reporting, or as a receipt to share with your group when collecting payment.

In Equal Split mode, you can enter any number of people from 1 to 100, making it useful for large event dinners or group outings where everyone paid the same share. In Proportional Split mode, the tool supports up to 8 individual bill amounts. For groups larger than 8 with unequal orders, you can group some people together and enter combined amounts, or use the equal split mode if everyone agreed to divide equally despite different orders.

Hair salon and spa tipping in the US typically runs 15% to 20% of the service cost. Some people tip the same percentage to the shampoo assistant as to the stylist; others tip $3 to $5 separately to assistants. At full-service spas for massages and facials, 20% is the widely accepted standard and reflects the physical labor involved. Many salons and spas include a tip line on their payment terminal; if you prefer to tip cash, inform the front desk so they can process the service charge portion separately.

Related Calculators You May Find Useful

🧾 Sales Tax Calculator Add or remove US sales tax for any purchase across all 50 states. 🏷️ Percent Off Calculator Find sale price, savings, or original price for any retail discount. 📊 Gross Margin Calculator Calculate profit margin on any product or service before and after tax. 💲 Markup Calculator Set your selling price from cost using any target markup percentage. 📈 Percentage Increase Calculator Find any percentage gain with step-by-step formula breakdown. 📉 Percentage Decrease Calculator Find the exact percentage drop between any two values. 🔄 Percentage Difference Calculator Compare two values using the symmetric midpoint formula. 🚗 Car Loan Calculator Estimate monthly payments and total interest on any US auto loan.

Legal Disclaimer and Editorial Transparency

The Tip Calculator and Bill Splitter on USCalculators.com is provided for educational and informational purposes only. All calculations use Big.js precision arithmetic. Tipping norms and percentages described on this page reflect general US cultural conventions and may vary by region, establishment type, and individual service quality. No calculation from this tool constitutes financial, legal, or tax advice.

Tip amounts are suggestions based on the percentage you select. Tipping is not legally required except where an establishment has added a mandatory service charge as a disclosed part of the bill. For information on tipped worker wages and employer obligations, refer to the US Department of Labor Wage and Hour Division. For federal tax treatment of tip income, refer to IRS Topic 761.

This content was written by the USCalculators.com editorial team to help American diners, travelers, and professionals navigate tipping culture with confidence and without the mental arithmetic that slows down an otherwise enjoyable meal. We do not accept payment to recommend any tipping level, service, or establishment. All tipping norms described are based on widely published US etiquette guidance and consumer behavior research.