body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: #333;
max-width: 800px;
margin: 0 auto;
padding: 20px;
}
.calculator-container {
background-color: #f8f9fa;
border: 1px solid #e9ecef;
border-radius: 8px;
padding: 25px;
margin-bottom: 40px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.calc-header {
text-align: center;
margin-bottom: 25px;
border-bottom: 2px solid #0056b3;
padding-bottom: 10px;
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #495057;
}
.input-group input, .input-group select {
width: 100%;
padding: 10px;
border: 1px solid #ced4da;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.input-group input:focus, .input-group select:focus {
border-color: #80bdff;
outline: 0;
box-shadow: 0 0 0 0.2rem rgba(0,123,255,.25);
}
.btn-calculate {
display: block;
width: 100%;
padding: 12px;
background-color: #0056b3;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: background-color 0.2s;
margin-top: 20px;
}
.btn-calculate:hover {
background-color: #004494;
}
#results {
margin-top: 25px;
background-color: #ffffff;
border: 1px solid #dee2e6;
border-radius: 4px;
padding: 20px;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
padding-bottom: 10px;
border-bottom: 1px solid #eee;
}
.result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.result-label {
color: #6c757d;
}
.result-value {
font-weight: bold;
color: #212529;
}
.final-total {
font-size: 1.5em;
color: #28a745;
}
.article-content {
margin-top: 40px;
}
.article-content h2 {
color: #2c3e50;
margin-top: 30px;
}
.article-content p {
margin-bottom: 15px;
}
.article-content ul {
margin-bottom: 20px;
}
.article-content li {
margin-bottom: 8px;
}
.rate-table {
width: 100%;
border-collapse: collapse;
margin: 20px 0;
}
.rate-table th, .rate-table td {
border: 1px solid #ddd;
padding: 12px;
text-align: left;
}
.rate-table th {
background-color: #f2f2f2;
}
How Is the Federal Mileage Rate Calculated?
Understanding how the federal mileage rate is calculated involves looking at two distinct processes: how the IRS determines the annual rate, and how taxpayers calculate their specific deduction or reimbursement using that rate. This guide explains the methodology behind the standard mileage rate and provides the current values for the 2023 and 2024 tax years.
1. How the IRS Determines the Standard Rate
The Internal Revenue Service (IRS) does not choose the mileage rate arbitrarily. Instead, they conduct an annual study of the fixed and variable costs of operating an automobile. This comprehensive analysis is often performed by an independent contractor, such as Runzheimer International.
To calculate the Business Standard Mileage Rate, the IRS considers factors such as:
- Fixed Costs: Depreciation, lease payments, insurance, registration fees, and license fees.
- Variable Costs: Gasoline (or electricity for EVs), oil changes, tires, and routine maintenance/repairs.
For the Medical and Moving rates, the calculation primarily focuses on variable costs (gas and oil), excluding most fixed costs like depreciation, as the car is personal property.
The Charitable rate is set by statute (law) and is not adjusted annually for inflation unless Congress passes specific legislation to change it. It has remained at 14 cents per mile for many years.
2. Current Federal Mileage Rates (2024 vs. 2023)
When calculating your deduction, it is critical to use the rate corresponding to the year the drive took place.
| Purpose |
2023 Rate |
2024 Rate |
| Business |
65.5 cents/mile |
67 cents/mile |
| Medical / Moving* |
22 cents/mile |
21 cents/mile |
| Charitable |
14 cents/mile |
14 cents/mile |
*Note: The moving deduction is currently suspended for most taxpayers under the Tax Cuts and Jobs Act, except for active-duty members of the Armed Forces moving under orders.
3. The Calculation Formula
To calculate your specific federal mileage deduction or reimbursement amount, the formula is straightforward:
Total Deduction = (Total Business Miles Driven) × (Standard Mileage Rate)
Example Calculation
If you drove your personal vehicle 1,200 miles for business purposes in 2024:
- Miles: 1,200
- 2024 Business Rate: $0.67
- Calculation: 1,200 × 0.67 = $804.00
This $804.00 represents the amount you can deduct from your taxable income or the tax-free reimbursement amount an employer can provide.
4. Standard Rate vs. Actual Expenses
Taxpayers generally have the option to choose between the Standard Mileage Rate and the Actual Expenses method. The Standard Rate is simpler, requiring you only to track the date, mileage, and business purpose of each trip. The Actual Expenses method requires tracking every receipt for gas, insurance, repairs, and depreciation, then multiplying the total cost by the percentage of business use.
Generally, the Standard Mileage Rate is preferred for older, fuel-efficient vehicles, while the Actual Expenses method may yield a higher deduction for newer, expensive vehicles with high depreciation or low fuel economy.
function calculateDeduction() {
// 1. Get DOM elements matching IDs exactly
var taxYearEl = document.getElementById("taxYear");
var tripPurposeEl = document.getElementById("tripPurpose");
var totalMilesEl = document.getElementById("totalMiles");
var resultsDiv = document.getElementById("results");
var displayRateEl = document.getElementById("displayRate");
var displayMilesEl = document.getElementById("displayMiles");
var totalDeductionEl = document.getElementById("totalDeduction");
// 2. Parse inputs
var year = parseInt(taxYearEl.value);
var purpose = tripPurposeEl.value;
var miles = parseFloat(totalMilesEl.value);
// 3. Define Rate Logic (Cents per mile converted to Dollars)
// Rates are hardcoded based on IRS publications for 2023 and 2024
var rate = 0;
if (year === 2024) {
if (purpose === "business") {
rate = 0.67; // 67 cents
} else if (purpose === "medical") {
rate = 0.21; // 21 cents
} else if (purpose === "charitable") {
rate = 0.14; // 14 cents
}
} else if (year === 2023) {
if (purpose === "business") {
rate = 0.655; // 65.5 cents
} else if (purpose === "medical") {
rate = 0.22; // 22 cents
} else if (purpose === "charitable") {
rate = 0.14; // 14 cents
}
}
// 4. Validate Input
if (isNaN(miles) || miles < 0) {
alert("Please enter a valid number of miles.");
return;
}
// 5. Calculate Total Deduction
var totalAmount = miles * rate;
// 6. Update UI
resultsDiv.style.display = "block";
displayMilesEl.textContent = miles.toLocaleString("en-US", { minimumFractionDigits: 0, maximumFractionDigits: 1 });
// Format rate to show cents clearly (e.g. $0.67)
displayRateEl.textContent = "$" + rate.toFixed(3); // Using 3 decimals for 2023 business rate (0.655)
// Format total to currency
totalDeductionEl.textContent = totalAmount.toLocaleString("en-US", {
style: "currency",
currency: "USD",
minimumFractionDigits: 2,
maximumFractionDigits: 2
});
}