Percentage of salary the plan covers (typically 60%).
The maximum amount the policy will pay per week.
Cost per $10 of weekly benefit (check your policy quote).
Gross Weekly Earnings:–
Calculated Weekly Benefit:–
Benefit Volume (Units of $10):–
Monthly Premium Cost:–
Annual Premium Cost:–
function calculateSTDPremium() {
// 1. Get input values
var salaryInput = document.getElementById('std_salary').value;
var percentInput = document.getElementById('std_percent').value;
var capInput = document.getElementById('std_cap').value;
var rateInput = document.getElementById('std_rate').value;
// 2. Parse values
var annualSalary = parseFloat(salaryInput);
var benefitPercent = parseFloat(percentInput);
var maxCap = parseFloat(capInput);
var ratePer10 = parseFloat(rateInput);
// 3. Validation
if (isNaN(annualSalary) || isNaN(benefitPercent) || isNaN(maxCap) || isNaN(ratePer10)) {
alert("Please enter valid numbers in all fields.");
return;
}
if (annualSalary <= 0 || benefitPercent maxCap) ? maxCap : potentialBenefit;
// Step D: Calculate Volume (Units of $10)
// Insurance rates are typically "per $10 of weekly benefit"
var benefitVolume = actualWeeklyBenefit / 10;
// Step E: Calculate Monthly Premium
var monthlyPremium = benefitVolume * ratePer10;
// Step F: Annual Cost
var annualPremium = monthlyPremium * 12;
// 5. Display Results
var resultsDiv = document.getElementById('std_results');
resultsDiv.style.display = 'block';
document.getElementById('res_weekly_earnings').innerText = '$' + weeklyEarnings.toFixed(2);
document.getElementById('res_weekly_benefit').innerText = '$' + actualWeeklyBenefit.toFixed(2);
// Explain if cap was hit
if (potentialBenefit > maxCap) {
document.getElementById('res_weekly_benefit').innerText += ' (Capped)';
}
document.getElementById('res_volume').innerText = benefitVolume.toFixed(2);
document.getElementById('res_monthly_premium').innerText = '$' + monthlyPremium.toFixed(2);
document.getElementById('res_annual_premium').innerText = '$' + annualPremium.toFixed(2);
}
Understanding Short Term Disability Rate Calculations
Short Term Disability (STD) insurance is a critical safety net that replaces a portion of your income if you are temporarily unable to work due to injury, illness, or childbirth. Unlike standard loans or simple purchases, calculating the premium for STD coverage involves a specific formula used by insurance underwriters.
How the Calculation Works
The cost of Short Term Disability insurance is not a flat fee. It is calculated based on how much income is being protected and the specific risk rate assigned to the policy. The formula generally follows these steps:
Determine Weekly Earnings: Since STD benefits are paid weekly, your annual salary is divided by 52.
Apply Benefit Percentage: Most plans cover 60% of your pre-disability earnings. This determines your potential weekly benefit.
Check the Benefit Cap: Policies have a "Maximum Weekly Benefit." If your calculated benefit exceeds this cap, the payout is limited to the cap amount.
Calculate Covered Volume: Insurance rates are often quoted "per $10 of weekly benefit." The benefit amount is divided by 10 to find the billable volume.
Apply the Rate: The covered volume is multiplied by the premium rate to determine the monthly cost.
Key Terms in the Calculator
Term
Definition
Covered Salary
The amount of your income that is eligible for insurance coverage, usually your base salary excluding bonuses.
Benefit Percentage
The portion of your salary the insurance will replace. The industry standard is usually 60%.
Maximum Cap
The absolute limit the insurance company will pay per week, regardless of your salary. Common caps range from $500 to $2,000.
Rate Per $10
The unit price of the insurance. For example, a rate of $0.50 means you pay 50 cents for every $10 of weekly benefit you receive.
Example Scenario
Let's look at a practical example to understand the math behind the Short Term Disability rate calculation:
Annual Salary: $52,000 (which is $1,000 per week)
Benefit Percentage: 60%
Maximum Cap: $1,000
Rate: $0.60 per $10 of benefit
Step 1: Calculate weekly benefit. $1,000 x 0.60 = $600.
Step 2: Check against cap. $600 is less than the $1,000 cap, so the full $600 is covered.
Step 3: Determine units of coverage. $600 / 10 = 60 units.
Step 4: Calculate premium. 60 units x $0.60 rate = $36.00 per month.
Why Do Rates Vary?
The "Rate per $10" is not arbitrary. It is influenced by several factors, including:
Age: Older employees typically have higher rates due to increased health risks.
Industry: High-risk industries (like construction) often have higher rates than office jobs.
Elimination Period: This is the waiting period before benefits begin (e.g., 7 days vs. 14 days). Shorter waiting periods result in higher premiums.
Benefit Duration: How long the policy pays out (e.g., 13 weeks vs. 26 weeks). Longer durations cost more.
Using the calculator above helps you estimate your payroll deductions or out-of-pocket costs for securing income protection.