For bartenders, bouncers, and retailers checking IDs.
To purchase alcohol legally, the customer must be born on or before:
Personal: When Can I Legally Drink?
Enter your birthdate to see your legal drinking date.
About the Drinking Age Calculator
Whether you are a bartender enforcing the law or an individual counting down the days until your 21st birthday, accuracy is paramount. This tool serves two distinct purposes: helping businesses verify age compliance and helping individuals determine exactly when they reach legal age.
For Retailers and Servers
In the United States, the legal minimum drinking age is 21. For businesses selling alcohol, calculating the "Born On or Before" date manually can lead to costly errors. A single mistake in math during a busy shift can result in fines, license suspension, or legal action.
The "Born On or Before" Logic: To determine if a customer is 21, you take the current date and subtract exactly 21 years. If the date on their ID is after this calculated date, they are underage. If it is on or before this date, they are legal.
Example: If today is October 15, 2023, and the legal age is 21.
Calculation: 2023 – 21 = 2002.
Result: The customer must have been born on or before October 15, 2002.
Midnight vs. Business Day Policies
While the law generally considers a person to be of age at 12:00 AM on the day of their birthday, many establishments have strict house policies. Some venues will not allow entry until the business day begins (e.g., they won't let you in at midnight if they close at 2 AM). Always verify specific state laws and establishment rules regarding "midnight 21st birthday" celebrations.
International Drinking Ages
While this calculator defaults to 21 (the US standard), you can adjust the input for other jurisdictions:
Age 18: Common in the UK, Australia, Canada (Alberta, Manitoba, Quebec), and much of Europe.
Age 19: Common in most Canadian provinces (Ontario, BC) and South Korea.
Age 20: Used in Japan and Thailand.
Age 21: Used in the USA, Egypt, and Indonesia.
Leap Year Considerations
Individuals born on February 29th (Leap Day) usually legally turn a year older on March 1st in non-leap years, though this can vary slightly by jurisdiction. This calculator uses standard calendar arithmetic to project the date.
// Set default date to today for the retailer section
var today = new Date();
var dd = String(today.getDate()).padStart(2, '0');
var mm = String(today.getMonth() + 1).padStart(2, '0'); // January is 0!
var yyyy = today.getFullYear();
var todayStr = yyyy + '-' + mm + '-' + dd;
document.getElementById('currentDate').value = todayStr;
function formatDateDisplay(dateObj) {
var options = { year: 'numeric', month: 'long', day: 'numeric' };
return dateObj.toLocaleDateString('en-US', options);
}
function calculateCutoffDate() {
var saleDateStr = document.getElementById('currentDate').value;
var ageLimit = parseInt(document.getElementById('legalAge').value);
var resultBox = document.getElementById('cutoffResult');
var display = document.getElementById('cutoffDisplay');
var subtext = document.getElementById('cutoffSubtext');
if (!saleDateStr || isNaN(ageLimit)) {
alert("Please enter a valid date and age limit.");
return;
}
// Create date object from input (append time to avoid timezone offset issues with pure dates)
var saleDate = new Date(saleDateStr + 'T00:00:00');
// Logic: Subtract years from the sale date
var cutoffDate = new Date(saleDate);
cutoffDate.setFullYear(cutoffDate.getFullYear() – ageLimit);
// Handle Leap Year edge case (Feb 29 -> Feb 28 in non-leap years via standard JS Date behavior,
// but legally often treated as March 1. JS auto-rolls Feb 29 to Mar 1 if non-leap year target)
// For simple "born on or before", standard Date behavior is usually sufficient for ID checks.
resultBox.style.display = 'block';
resultBox.style.backgroundColor = '#f1f8e9';
resultBox.style.borderColor = '#c5e1a5';
display.innerHTML = formatDateDisplay(cutoffDate);
display.style.color = '#2e7d32';
subtext.innerHTML = "If their ID shows a birthdate after this date, sale is prohibited.";
}
function calculatePersonalEligibility() {
var birthDateStr = document.getElementById('userBirthDate').value;
var targetAge = parseInt(document.getElementById('userTargetAge').value);
var resultBox = document.getElementById('personalResult');
var header = document.getElementById('eligibilityHeader');
var display = document.getElementById('eligibilityDate');
var countdown = document.getElementById('eligibilityCountdown');
if (!birthDateStr || isNaN(targetAge)) {
alert("Please enter your birth date and target age.");
return;
}
var birthDate = new Date(birthDateStr + 'T00:00:00');
var now = new Date();
// Zero out time for accurate day comparison
now.setHours(0,0,0,0);
// Calculate when they turn the target age
var legalDate = new Date(birthDate);
legalDate.setFullYear(legalDate.getFullYear() + targetAge);
resultBox.style.display = 'block';
display.innerHTML = formatDateDisplay(legalDate);
// Compare dates
if (now >= legalDate) {
// Already legal
resultBox.style.backgroundColor = '#e8f5e9'; // Greenish
resultBox.style.borderColor = '#a5d6a7';
header.innerHTML = "You are currently LEGAL to drink.";
display.style.color = '#2e7d32';
// Calculate how long ago
var diffTime = Math.abs(now – legalDate);
var diffDays = Math.ceil(diffTime / (1000 * 60 * 60 * 24));
countdown.innerHTML = "You turned " + targetAge + " exactly " + diffDays + " days ago.";
} else {
// Not legal yet
resultBox.style.backgroundColor = '#ffebee'; // Reddish
resultBox.style.borderColor = '#ef9a9a';
header.innerHTML = "You are currently NOT LEGAL.";
display.style.color = '#c62828';
// Calculate countdown
var diffTime = Math.abs(legalDate – now);
var diffDays = Math.ceil(diffTime / (1000 * 60 * 60 * 24));
// Detailed countdown logic
var years = legalDate.getFullYear() – now.getFullYear();
var m = legalDate.getMonth() – now.getMonth();
if (m < 0 || (m === 0 && legalDate.getDate() < now.getDate())) {
years–;
}
countdown.innerHTML = "Wait Time: " + diffDays + " days left.(Or approx " + years + " years).";
}
}