HELOC Calculator

About the HELOC Calculator

A Home Equity Line of Credit, commonly called a HELOC, is a revolving credit facility secured by a homeowner's property. Unlike a traditional home equity loan that generally provides a fixed lump sum, a HELOC allows the borrower to access funds up to an approved credit limit during a draw period. The amount of interest paid depends on the amount borrowed and the applicable interest rate, while the payment structure can change when the account moves from the draw period into the repayment period.

HELOCs commonly have two main phases. During the draw period, borrowers may be able to borrow, repay, and borrow again up to the available credit limit. Depending on the agreement, payments during this period may be based primarily on interest. During the repayment period, additional borrowing may be restricted and payments generally include both principal and interest. Because many HELOCs use variable interest rates, the actual payment and total borrowing cost can change when the interest rate changes.

This HELOC Calculator estimates available home equity, current loan-to-value ratio, combined loan-to-value ratio, monthly interest during the draw period, estimated repayment-period payment, total repayment-period interest, and total estimated interest based on the assumptions entered. It does not determine lender approval, the maximum credit limit available to a borrower, or the exact terms of a particular HELOC agreement.

How the HELOC Calculator Works

The calculator first estimates home equity by subtracting the current mortgage balance from the home's value. It then combines the existing mortgage balance with the proposed HELOC amount to estimate the resulting combined loan-to-value ratio.

The calculator estimates interest-only payments during the draw period using the entered HELOC balance and interest rate. It then estimates an amortizing monthly payment during the repayment period using the HELOC amount, interest rate, and repayment period.

What This HELOC Calculator Calculates

The calculator estimates current home equity, current loan-to-value ratio, combined loan-to-value ratio, estimated equity after the HELOC, monthly draw-period interest, annual draw-period interest, estimated repayment-period payment, total repayment-period payments, repayment-period interest, and total estimated interest.

Home Equity

Home equity represents the estimated portion of the property's value that is not covered by the existing mortgage balance.

Home Equity = Home Value − Current Mortgage Balance

For example, a $350,000 property with a $200,000 mortgage balance has estimated equity of $150,000.

Current Loan-to-Value Ratio

Current loan-to-value ratio compares the outstanding mortgage balance with the current property value.

Current LTV = Current Mortgage Balance ÷ Home Value × 100

A $200,000 mortgage balance on a $350,000 property produces a current LTV of approximately 57.14%.

Combined Loan-to-Value Ratio

A HELOC creates additional debt secured by the property. Combined LTV measures the existing mortgage plus the HELOC balance relative to the property's value.

Combined LTV = (Current Mortgage Balance + HELOC Amount) ÷ Home Value × 100

With a $200,000 mortgage and a $50,000 HELOC on a $350,000 property, the estimated combined LTV is 71.43%.

HELOC Draw Period

The draw period is the period during which the borrower may generally access available credit under the HELOC agreement. The borrower may be able to draw funds, repay part of the balance, and borrow again as permitted by the lender.

This calculator assumes that the full HELOC amount entered remains outstanding during the draw period and estimates the monthly interest using the entered interest rate.

Draw-Period Interest

The estimated monthly interest during the draw period is calculated by applying the annual interest rate to the outstanding HELOC balance and dividing the result by 12.

Monthly Draw Interest = HELOC Amount × Interest Rate ÷ 12

For a $50,000 balance at an 8% annual interest rate, the estimated monthly interest is approximately $333.33.

HELOC Repayment Period

After the draw period ends, a HELOC generally enters a repayment period. Depending on the agreement, the borrower may no longer be able to make additional draws and the outstanding balance is repaid over the selected repayment period.

This calculator estimates the repayment payment using a standard amortizing loan formula, assuming the entered HELOC balance is repaid over the full repayment period at the entered interest rate.

Repayment-Period Payment Formula

Monthly Payment = P × r × (1 + r)n ÷ ((1 + r)n − 1)

In this formula, P represents the HELOC balance, r represents the monthly interest rate, and n represents the total number of repayment-period monthly payments.

Total HELOC Interest

Estimated total interest combines the estimated interest paid during the draw period with the estimated interest paid during the repayment period.

Total Estimated Interest = Draw-Period Interest + Repayment-Period Interest

The calculation assumes that the full HELOC balance remains outstanding throughout the draw period and that the interest rate remains unchanged. Actual HELOC interest can differ substantially when the rate changes or the outstanding balance changes.

Effect of a Larger HELOC

Increasing the HELOC amount generally increases the estimated monthly interest during the draw period and increases the repayment-period payment. It also increases the combined loan-to-value ratio and reduces the estimated equity remaining in the property.

Effect of a Higher Interest Rate

A higher interest rate increases the estimated interest charged on the outstanding HELOC balance. Because HELOC rates can be variable, changes in the rate can affect both draw-period interest and repayment-period payments.

Effect of a Longer Repayment Period

A longer repayment period generally reduces the required monthly payment by spreading repayment over more months. However, keeping the balance outstanding for longer can increase the total interest paid.

HELOC vs. Home Equity Loan

A HELOC is generally a revolving line of credit that allows borrowing as needed up to a credit limit, while a home equity loan generally provides a fixed amount of money at the beginning of the loan. A home equity loan commonly has a more predictable repayment schedule, whereas a HELOC can provide greater borrowing flexibility but may involve a variable interest rate.

HELOC vs. Cash-Out Refinance

A cash-out refinance replaces an existing mortgage with a new mortgage that is larger than the current balance, with the difference generally provided as cash to the borrower. A HELOC instead adds a separate line of credit secured by the property while the existing mortgage generally remains in place.

Property Value and HELOC Borrowing

Property value plays an important role in determining the amount of secured debt that may be supported by a property. An increase in property value can improve the estimated equity position and reduce the combined LTV, while a decrease in property value can have the opposite effect.

HELOC Fees and Costs

A HELOC may involve costs such as application fees, appraisal charges, closing costs, annual fees, transaction fees, early termination fees, or other lender charges. These costs vary by lender and are not included in the basic calculations provided by this tool.

Variable Interest Rates

Many HELOCs use variable interest rates. If the rate changes, the amount of interest charged on the outstanding balance can also change. This means the actual payment and total borrowing cost may differ from the estimate shown by a calculator using a single fixed rate assumption.

Understanding the Results

Home Equity represents the estimated difference between the property value and the current mortgage balance. Current LTV measures the existing mortgage relative to the property value. Combined LTV includes both the existing mortgage and the proposed HELOC amount.

Draw-Period Monthly Interest represents the estimated interest charged each month while the entered HELOC balance remains outstanding during the draw period. Repayment-Period Payment represents the estimated monthly payment required to amortize the HELOC balance during the repayment period.

Frequently Asked Questions

What is a HELOC?

A HELOC is a revolving line of credit secured by a property. It allows eligible borrowers to access funds up to an approved credit limit.

How is HELOC interest calculated?

Estimated interest is based on the outstanding balance and applicable interest rate. This calculator assumes the entered HELOC amount remains outstanding during the draw period.

Does a HELOC use my home as collateral?

Yes. A HELOC is generally secured by the property. Failure to meet required payments can therefore create serious consequences for the borrower.

What is the draw period?

The draw period is the period during which the borrower may generally access available credit under the terms of the HELOC.

What is the repayment period?

The repayment period is the period during which the outstanding balance is repaid. Additional borrowing may be restricted depending on the agreement.

Does this calculator assume a variable interest rate?

No. The calculator uses the entered interest rate as a constant assumption for estimating the results. Actual HELOC rates may change over time.

Does this calculator determine the maximum HELOC I can get?

No. Maximum borrowing limits depend on lender requirements, property value, combined LTV limits, credit, income, debt obligations, and other factors.

Does this calculator include my existing mortgage payment?

No. The calculations focus on the HELOC balance and do not include the payment required for the existing mortgage.

Does this calculator include closing costs?

No. Lender fees, appraisal costs, closing costs, annual fees, and other charges are not included.

Is a HELOC the same as a home equity loan?

No. A HELOC is generally revolving credit, while a home equity loan usually provides a fixed lump-sum amount with scheduled repayment.

Can a HELOC payment change?

Yes. Actual HELOC payments can change because interest rates may vary and the outstanding balance can change as the borrower draws or repays funds.

Does a larger HELOC increase my combined LTV?

Yes. A larger HELOC balance increases the total debt secured by the property and therefore increases the combined LTV when the property value remains unchanged.

Limitations of the HELOC Calculator

This calculator provides a simplified estimate based on the home value, current mortgage balance, HELOC amount, interest rate, draw period, and repayment period entered by the user. It assumes that the full HELOC amount remains outstanding during the draw period and that the entered interest rate remains unchanged.

Actual HELOC agreements can use variable interest rates, different payment structures, minimum payment requirements, changing balances, lender-specific fees, annual fees, draw restrictions, and other terms that can affect the actual cost of borrowing.

The calculator does not determine lender approval, available credit limits, eligibility, credit requirements, property-specific borrowing limits, closing costs, taxes, insurance, or other transaction expenses. The results are estimates intended to help users understand basic HELOC borrowing mathematics and compare scenarios.