Free Home Loan Tool

Mortgage Payment
Calculator

Q: How is a mortgage payment calculated?

The mortgage payment formula is: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan amount, r is the monthly interest rate (annual rate divided by 12 then by 100), and n is the total number of monthly payments. For a S$640,000 loan at 3.5% for 25 years: monthly rate = 0.002917, n = 300, and the monthly payment = approximately S$3,204. This calculator applies this formula automatically as you enter your values.

Q: What is a good mortgage interest rate?

Interest rates vary significantly by market, economic conditions, loan type, and borrower profile. In Singapore (2024–2025 environment), fixed rates range from approximately 2.5–4% for 1–2 year fixed periods, while floating SORA-based rates have ranged from 2.5–4.5%. Globally, what constitutes a “good rate” depends on the prevailing central bank rate environment. The key comparison is against rates from multiple lenders, even 0.25% lower than average over a 25-year loan saves tens of thousands in total interest. Always compare rates from at least 3–5 lenders before committing.

Q: How much can I afford to borrow for a mortgage?

In Singapore, MAS regulations cap mortgage repayments at 30% of gross income for HDB loans (MSR) and total debt servicing (including all loans) at 55% of gross income (TDSR). A practical guideline: your monthly mortgage payment should not exceed 28% of gross monthly income. For a household earning S$12,000/month, the maximum comfortable mortgage payment is approximately S$3,360. Use the calculator to find the loan amount that produces a payment within this threshold, then work backward to your maximum affordable home price.

Q: What is amortization?

Amortization is the process of paying off a loan through regular scheduled payments that cover both principal and interest. In an amortizing mortgage, early payments are mostly interest and later payments become mostly principal, though the total monthly payment stays constant. The amortization schedule (shown in the table above) maps out every payment’s exact split between principal and interest, and shows the remaining balance after each payment period. This makes it possible to see exactly how much loan you still owe at any point in the loan term.

Q: What is PMI and when do I need it?

PMI (Private Mortgage Insurance) is an insurance policy required by most lenders when your down payment is less than 20% of the property value. It protects the lender (not you) against default losses. PMI typically costs 0.5–1.5% of the loan amount annually (S$3,200–9,600/year on a S$640,000 loan). In Singapore, MAS-regulated banks require borrowers to insure the property against fire and structural risks, and MiHomes (the HLAS insurance) provides similar coverage for HDB mortgages. PMI as commonly understood in US markets is not an identical concept in Singapore, check with your specific lender.

Q: Should I choose a shorter or longer mortgage term?

The optimal term depends on your monthly cash flow versus total cost priorities. A 15-year term has higher monthly payments but dramatically lower total interest, typically 30–40% less. A 30-year term has lower monthly payments, preserving cash flow for other priorities, but doubles or triples total interest paid. If you can afford the higher monthly payment of a shorter term, the long-term savings are substantial. A middle approach: take the longer term but make extra payments consistently, you get the safety net of a lower required payment with the interest savings of a shorter effective term.

Q: How do extra mortgage payments work?

Extra payments go entirely toward reducing your principal balance rather than splitting between principal and interest like regular payments. Because mortgage interest is calculated on the outstanding balance, a lower balance immediately reduces the interest portion of every subsequent payment, creating a compounding benefit. An extra S$300/month on a 25-year S$640,000 mortgage at 3.5% saves approximately S$45,800 in total interest and reduces the loan term by about 3.2 years. Always designate extra payments as “additional principal” when paying, not as early payment of next month’s regular installment.

Q: What is LTV (Loan-to-Value) and why does it matter?

LTV (Loan-to-Value) ratio is the loan amount divided by the property value, expressed as a percentage. A S$640,000 loan on an S$800,000 property = 80% LTV. LTV matters because: (1) lenders use it to assess risk, higher LTV means higher risk, often resulting in higher interest rates or stricter requirements; (2) in Singapore, MAS rules cap LTV at 75% for most private property loans from financial institutions; (3) a lower LTV (larger down payment) typically results in better loan terms, no PMI requirement, and lower total borrowing costs.

Q: When should I refinance my mortgage?

Refinancing makes financial sense when: (1) current rates are at least 0.5–1% lower than your existing rate; (2) you plan to stay in the property long enough to recoup the refinancing costs through lower payments; (3) your lock-in period has ended (refinancing during lock-in typically incurs penalties of 0.75–1.5% of outstanding loan amount); (4) your property value has increased enough to improve your LTV ratio. In Singapore, most homeowners refinance every 2–3 years at the end of their fixed-rate lock-in period. Use a break-even calculation: divide total refinancing costs by monthly payment savings to find how many months it takes to come out ahead.

Q: How accurate is this mortgage calculator?

This calculator applies the mathematically exact standard mortgage formula and produces precisely accurate results for fixed-rate mortgages with constant monthly payments. It does not account for: variable rate changes over time, loan fees and closing costs (which increase the effective interest rate), CPF usage and OA balance interaction, property price appreciation or depreciation, or changes in tax rates and insurance premiums. For a complete financial analysis of a specific mortgage product, consult the bank’s loan document and a licensed mortgage adviser.

Estimate your monthly home loan payment, total interest cost, and full amortization schedule, instantly. Includes property tax, insurance, and PMI options.

Instant Results

Amortization Breakdown

Accurate Estimates

Calculate Your Mortgage Payment

Enter your home details below. Your monthly payment and full cost breakdown update instantly as you type.

Currency

Home price / property value

Down payment

Minimum 10% for most lenders; below 20% may require PMI

Annual interest rate (%)

Loan term (years)

Optional monthly costs leave blank to exclude

Property tax (annual)

Home insurance (annual)

PMI (annual, if <20% down)

Early payoff (optional)

Extra monthly payment Additional principal payment per month, reduces total interest and term

Monthly mortgage payment

—

⚠️ Down payment below 20%: You may be required to pay Private Mortgage Insurance (PMI), typically 0.5 to 1.5% of the loan amount annually. Enter the annual PMI cost above to include it in your monthly payment.

Loan amount

—

Down payment

—

Total interest

—

Total cost

—

Property tax

—

Home insurance

—

PMI

—

Base P&I payment —

Principal vs interest split

—

Year	Principal paid	Interest paid	Remaining balance

💡 Mortgage insights:
—

⚠️ Disclaimer: This calculator provides estimates for educational purposes only. Actual mortgage terms, rates, and conditions vary by lender and individual circumstances. Always consult a licensed mortgage adviser or bank before making home financing decisions.

Mortgage Payment Calculator: Estimate Your Monthly Home Loan Costs

Buying a home is almost certainly the largest financial decision you will ever make. Before you make an offer, sign a contract, or choose between loan packages, you need to understand one critical number: your monthly mortgage payment. This free mortgage payment calculator gives you that number instantly, along with your total interest cost, a full amortization breakdown, and the impact of extra payments: so you can plan with complete clarity before you commit.

Quick answer: Your monthly mortgage payment depends on loan amount, interest rate, and loan term. For a S$640,000 loan (S$800,000 home, 20% down) at 3.5% over 25 years, the monthly payment is approximately S$3,204. The total interest paid over the life of the loan is approximately S$321,200. Use the calculator above for your personalised figures.

What Is a Mortgage Payment?

A mortgage payment is the regular amount you pay to your lender each month to repay a home loan. Standard mortgage payments consist of two components: principal (repayment of the actual loan amount) and interest (the lender’s charge for lending the money). In the early years of a mortgage, the majority of each payment goes toward interest, a distribution that gradually shifts toward principal as the loan matures.

In addition to the core principal and interest (P&I) payment, your total monthly housing cost may include:

Property tax: In Singapore, Annual Value (AV)-based property tax is payable. In other markets, property taxes are often collected monthly by lenders through an escrow account.
Home insurance: Typically required by lenders to protect the property against fire, natural disaster, and liability.
PMI (Private Mortgage Insurance): Required by many lenders when the down payment is below 20%. Protects the lender (not you) against default.

This calculator includes all four components, giving you a complete picture of your true monthly housing cost, not just the headline mortgage figure quoted in advertisements.

How the Mortgage Payment Calculator Formula Works

This calculator measures the fixed monthly payment that fully repays a loan over a set number of years, given a constant interest rate. It’s called an annuity formula because it calculates equal periodic payments that pay off the loan exactly, with nothing owed and nothing left over, at the end of the term.

M = P × [r(1+r)^n] / [(1+r)^n − 1]

Where:
M = Monthly payment
P = Principal (loan amount)
r = Monthly interest rate (annual rate ÷ 12 ÷ 100)
n = Total number of monthly payments (years × 12)

P is your loan amount, the home price minus your down payment. r is your annual interest rate converted to a monthly decimal. n is your loan term in months. The result, M, stays fixed for the entire loan if your rate is fixed, but the split between principal and interest within each payment shifts over time, which is exactly what the amortization chart and table above show.

Step-by-step calculation walkthrough

Step 1: Identify the inputs. Loan amount: S$640,000. Annual interest rate: 3.5%. Loan term: 25 years (300 months).

Step 2: Apply the formula. Monthly rate = 3.5 ÷ 12 ÷ 100 = 0.002917. Number of payments = 25 × 12 = 300. M = 640,000 × [0.002917 × (1.002917)^300] ÷ [(1.002917)^300 − 1].

Step 3: Perform the calculation. Working through the exponents and division gives a monthly payment of S$3,204. Over 300 payments, total repayment comes to S$961,200, of which S$321,200 is interest and S$640,000 is the original principal.

Step 4: Interpret the result. This S$640,000 loan costs S$3,204 a month for 25 years straight, with the payment amount never changing (assuming a fixed rate). Total interest of S$321,200 works out to just over 50% of the amount borrowed, which is why the loan term and interest rate matter as much as the headline monthly figure when comparing offers.

📐 The donut chart, principal-versus-interest bar, and amortization table shown in your results all read from this same fixed monthly payment. Adding extra payments doesn’t change this formula, it runs an additional simulation on top that applies your extra amount directly to principal each month, which is how the calculator determines your reduced total interest and shortened term.

Assumptions and limitations: the formula is exact given a fixed rate for the entire term, but it assumes the rate never changes, which doesn’t hold for floating or variable-rate mortgages once any initial fixed period ends. It also calculates principal and interest only, property tax, insurance, and PMI are added on top as separate inputs rather than derived from the loan itself. Real closing costs, lender fees, and exact local compounding conventions can shift the numbers your actual bank quotes slightly from this calculator’s estimate.

Principal vs Interest Explained

Understanding how your payment is split between principal and interest is crucial for appreciating the true cost of homeownership. In a typical 25-year mortgage at 3.5%:

Month 1: Of a S$3,204 payment, approximately S$1,867 goes to interest and only S$1,337 reduces the principal balance
Year 10: The split shifts: roughly S$1,372 to interest and S$1,832 to principal
Year 25 (final year): Almost entirely principal repayment: interest is minimal

This front-loading of interest explains why the total interest paid over a 25-year mortgage can equal 40 to 60% of the original loan amount. A S$640,000 loan at 3.5% over 25 years costs S$321,200 in interest alone, making the true cost of the loan nearly S$961,200 on top of the S$160,000 down payment already paid.

What Affects Your Monthly Mortgage Payment

Factor	Effect on monthly payment	Example impact
Higher loan amount	Increases payment proportionally	+S$100K loan → +S$500/mo (approx.)
Higher interest rate	Significantly increases payment + total interest	+1% rate on S$640K → +S$353/mo
Longer loan term	Decreases monthly but increases total interest	30yr vs 25yr → −S$330/mo but +S$73K interest
Larger down payment	Reduces loan amount and total interest	25% vs 20% down → −S$200/mo
Extra monthly payment	Reduces term and total interest	+S$300/mo → saves years + thousands in interest

How Much House Can You Afford?

Mortgage affordability is governed by two widely-used rules that help lenders and borrowers assess sustainable debt levels:

The 28% Rule

Your monthly housing costs (principal, interest, taxes, and insurance, PITI) should not exceed 28% of your gross monthly income. A household with a S$12,000/month gross income should target a maximum monthly housing cost of approximately S$3,360.

The 36% Rule (Total Debt)

Your total monthly debt obligations (mortgage plus car loans, student loans, credit cards, and other debts) should not exceed 36% of gross monthly income. In Singapore, the Mortgage Servicing Ratio (MSR) limits HDB loan repayments to 30% of gross income, while the Total Debt Servicing Ratio (TDSR) caps all loan obligations at 55% of gross income.

Singapore-Specific Frameworks

MSR (Mortgage Servicing Ratio): For HDB loans, maximum 30% of gross monthly income
TDSR (Total Debt Servicing Ratio): Maximum 55% of gross monthly income for all debt obligations
LTV (Loan-to-Value) limits: For first HDB loan: up to 75% LTV; for private property loans: 75% for first loan, reducing for subsequent loans
ABSD (Additional Buyer’s Stamp Duty): Additional costs ranging from 5–60% depending on citizenship status and number of properties owned

Fixed vs Variable Interest Rates

One of the most consequential decisions in mortgage planning is whether to choose a fixed or variable (floating) interest rate:

Feature	Fixed rate	Variable/floating rate
Rate stability	Constant throughout fixed period	Fluctuates with market benchmark
Initial rate	Usually slightly higher	Usually slightly lower
Typical lock-in	1–5 years (Singapore banks)	None or short term
Best in environment	Rising interest rate environment	Falling interest rate environment
Risk	Rate may be above market after lock-in	Rate may rise significantly
Planning certainty	High, exact monthly cost known	Low, payment can change

In Singapore, most mortgages use a floating rate pegged to benchmarks like SORA (Singapore Overnight Rate Average), the official interest rate benchmark administered by MAS, plus a bank spread. Fixed-rate periods of 1 to 5 years are available, after which the loan reverts to a floating rate. Given rate volatility in recent years, many borrowers choose short fixed-rate periods (1 to 2 years) to reduce conversion costs while maintaining some near-term certainty.

Extra Payments and Early Payoff Strategy

Making additional principal payments above your required monthly payment is one of the most powerful mortgage management strategies available. The impact is significant because mortgage interest is calculated on the outstanding balance, reducing the balance faster means less interest accrues in subsequent months:

Extra payment example: On a S$640,000 loan at 3.5% over 25 years, paying an extra S$300/month:
Saves approximately S$45,800 in total interest
Reduces loan term by approximately 3.2 years
Requires only S$300/month extra, equivalent to a modest lifestyle reduction

In Singapore, most mortgage packages allow partial capital repayment (PCR) up to a specified annual limit without penalty during lock-in periods. Outside lock-in periods, unlimited extra payments are typically permitted. Always check your loan package terms before making significant extra payments to avoid prepayment penalties.

How to Reduce Your Mortgage Costs

💰

Increase your down payment

Each additional 5% down payment reduces your loan principal and monthly payment, eliminates or reduces PMI, and saves significantly on total interest over the loan term. Saving an extra S$40,000 down can save approximately S$20,000 in total interest.

🏦

Shop multiple lenders

Even a 0.25% difference in interest rate on S$640,000 over 25 years saves approximately S$25,500 in total interest. Request loan estimates from at least 3 lenders and compare full cost of credit, not just the headline rate.

⏱️

Consider a shorter loan term

A 20-year vs 25-year mortgage on S$640,000 at 3.5% costs S$508/month more but saves approximately S$70,400 in total interest. If affordable, shorter terms produce dramatic total cost savings.

📅

Refinance at the right time

Refinancing to a lower rate when it drops can reduce both monthly payments and total interest. In Singapore, refinance to a different bank after the lock-in period to access competitive rates, typically every 2–3 years for active rate shoppers.

➕

Make regular extra payments

Even S$100–200 extra per month reduces total interest by tens of thousands over a 25-year loan. The earlier in the loan these extra payments are made, the greater their impact due to the remaining compounding period.

🎯

Time your purchase wisely

Buying when interest rates are lower dramatically reduces lifetime mortgage costs. A 1% lower rate on S$640,000 over 25 years saves approximately S$99,900 in total interest, equivalent to reducing the home price by that amount.

Mortgage Calculator vs Real Loan Estimates

This calculator provides accurate estimates based on the standard mortgage formula, but several factors mean real loan offers will differ:

Fees and charges: Origination fees, legal fees, valuation fees, and stamp duties add to the effective cost of borrowing. In Singapore, Buyer’s Stamp Duty (BSD) starts at 1% for the first S$180,000 and rises progressively.
Rate lock periods: Fixed rates apply only during the lock-in period; the rate (and therefore payment) changes on reversion to floating.
Floating rate variability: Variable rate mortgages have payments that change with market benchmark movements, making long-term projections inherently approximate.
CPF usage: Singapore citizens and PRs can use CPF Ordinary Account (OA) balances for down payment and monthly repayments, reducing cash requirements. This calculator does not model CPF, consult your bank for the integrated picture.

3 Real-Life Examples

Three different homebuying situations, calculated the way the tool above does it.

Situation	Inputs	Result	What it means
First-time buyer with a 10% down payment	S$450,000 home, 10% down, S$405,000 loan, 4.0% rate, 25-year term.	Monthly payment: S$2,138. Total interest: S$236,322.	With only 10% down, PMI likely applies on top of this monthly figure, and the higher rate compared to a 20%-down buyer reflects the lender’s added risk at this loan-to-value ratio.
Buying a higher-value condo with a larger down payment	S$1,200,000 home, 25% down, S$900,000 loan, 3.2% rate, 30-year term.	Monthly payment: S$3,892. Total interest: S$501,193.	The larger down payment and lower rate keep the monthly payment proportionally more manageable relative to the loan size, but the 30-year term still means total interest exceeds half the loan amount.
Comparing a 20-year term to a 30-year term on the same loan	S$550,000 loan at 3.8%, comparing 20-year and 30-year terms.	20-year: S$3,275/month, S$236,052 total interest. 30-year: S$2,563/month, S$372,596 total interest.	The 20-year term costs about S$712 more per month but saves roughly S$136,500 in interest overall, the same monthly-payment-versus-total-cost trade-off that runs through every term decision.

These are illustrative calculations using the same formula the calculator above applies. They’re a planning tool, not a substitute for an actual loan offer from a lender.

Important Notes

These are simulated projections, not a loan offer. The formula is exact given a fixed rate and term, but actual approval, rate, and terms depend on your lender and creditworthiness.
Rounding. Displayed currency figures round to the nearest whole unit, or abbreviate to K, M, or B for large values.
This calculator assumes a fixed rate for the full term. Floating and variable-rate mortgages change over time, rerun the calculator at different rates to see the range of possible payments if your rate isn’t fixed.
Property tax, insurance, and PMI are entered separately, not derived from the loan. These are estimates you supply, get actual figures from your insurer, local tax authority, and lender before finalizing a budget.
Closing costs and lender fees aren’t included. These add to the effective cost of borrowing beyond the principal and interest shown here.
Extra payments assume they’re applied directly to principal. Always confirm with your lender that extra payments are designated as additional principal, not as an early payment of the next installment, which wouldn’t reduce total interest the same way.
Data privacy. All calculations run in your browser. Your inputs aren’t sent to a server, and the PDF is generated locally on your device.

Related Financial Calculators

Frequently Asked Questions

How is a mortgage payment calculated?

The mortgage payment formula is: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan amount, r is the monthly interest rate (annual rate divided by 12 then by 100), and n is the total number of monthly payments. For a S$640,000 loan at 3.5% for 25 years: monthly rate = 0.002917, n = 300, and the monthly payment = approximately S$3,204. This calculator applies this formula automatically as you enter your values.

What is a good mortgage interest rate?

Interest rates vary significantly by market, economic conditions, loan type, and borrower profile. In Singapore (2024–2025 environment), fixed rates range from approximately 2.5–4% for 1–2 year fixed periods, while floating SORA-based rates have ranged from 2.5–4.5%. Globally, what constitutes a “good rate” depends on the prevailing central bank rate environment. The key comparison is against rates from multiple lenders, even 0.25% lower than average over a 25-year loan saves tens of thousands in total interest. Always compare rates from at least 3–5 lenders before committing.

How much can I afford to borrow for a mortgage?

In Singapore, MAS regulations cap mortgage repayments at 30% of gross income for HDB loans (MSR) and total debt servicing (including all loans) at 55% of gross income (TDSR). A practical guideline: your monthly mortgage payment should not exceed 28% of gross monthly income. For a household earning S$12,000/month, the maximum comfortable mortgage payment is approximately S$3,360. Use the calculator to find the loan amount that produces a payment within this threshold, then work backward to your maximum affordable home price.

What is amortization?

Amortization is the process of paying off a loan through regular scheduled payments that cover both principal and interest. In an amortizing mortgage, early payments are mostly interest and later payments become mostly principal, though the total monthly payment stays constant. The amortization schedule (shown in the table above) maps out every payment’s exact split between principal and interest, and shows the remaining balance after each payment period. This makes it possible to see exactly how much loan you still owe at any point in the loan term.

What is PMI and when do I need it?

PMI (Private Mortgage Insurance) is an insurance policy required by most lenders when your down payment is less than 20% of the property value. It protects the lender (not you) against default losses. PMI typically costs 0.5–1.5% of the loan amount annually (S$3,200–9,600/year on a S$640,000 loan). In Singapore, MAS-regulated banks require borrowers to insure the property against fire and structural risks, and MiHomes (the HLAS insurance) provides similar coverage for HDB mortgages. PMI as commonly understood in US markets is not an identical concept in Singapore, check with your specific lender.

Should I choose a shorter or longer mortgage term?

The optimal term depends on your monthly cash flow versus total cost priorities. A 15-year term has higher monthly payments but dramatically lower total interest, typically 30–40% less. A 30-year term has lower monthly payments, preserving cash flow for other priorities, but doubles or triples total interest paid. If you can afford the higher monthly payment of a shorter term, the long-term savings are substantial. A middle approach: take the longer term but make extra payments consistently, you get the safety net of a lower required payment with the interest savings of a shorter effective term.

How do extra mortgage payments work?

Extra payments go entirely toward reducing your principal balance rather than splitting between principal and interest like regular payments. Because mortgage interest is calculated on the outstanding balance, a lower balance immediately reduces the interest portion of every subsequent payment, creating a compounding benefit. An extra S$300/month on a 25-year S$640,000 mortgage at 3.5% saves approximately S$45,800 in total interest and reduces the loan term by about 3.2 years. Always designate extra payments as “additional principal” when paying, not as early payment of next month’s regular installment.

What is LTV (Loan-to-Value) and why does it matter?

LTV (Loan-to-Value) ratio is the loan amount divided by the property value, expressed as a percentage. A S$640,000 loan on an S$800,000 property = 80% LTV. LTV matters because: (1) lenders use it to assess risk, higher LTV means higher risk, often resulting in higher interest rates or stricter requirements; (2) in Singapore, MAS rules cap LTV at 75% for most private property loans from financial institutions; (3) a lower LTV (larger down payment) typically results in better loan terms, no PMI requirement, and lower total borrowing costs.

When should I refinance my mortgage?

Refinancing makes financial sense when: (1) current rates are at least 0.5–1% lower than your existing rate; (2) you plan to stay in the property long enough to recoup the refinancing costs through lower payments; (3) your lock-in period has ended (refinancing during lock-in typically incurs penalties of 0.75–1.5% of outstanding loan amount); (4) your property value has increased enough to improve your LTV ratio. In Singapore, most homeowners refinance every 2–3 years at the end of their fixed-rate lock-in period. Use a break-even calculation: divide total refinancing costs by monthly payment savings to find how many months it takes to come out ahead.

How accurate is this mortgage calculator?

This calculator applies the mathematically exact standard mortgage formula and produces precisely accurate results for fixed-rate mortgages with constant monthly payments. It does not account for: variable rate changes over time, loan fees and closing costs (which increase the effective interest rate), CPF usage and OA balance interaction, property price appreciation or depreciation, or changes in tax rates and insurance premiums. For a complete financial analysis of a specific mortgage product, consult the bank’s loan document and a licensed mortgage adviser.

Why does the amortization table only show yearly totals?

The table summarizes each year’s principal paid, interest paid, and remaining balance rather than listing all 300 or more individual monthly payments, which keeps the schedule readable while still showing exactly how the principal-versus-interest split shifts year by year. The underlying calculation still runs month by month internally, the yearly view is just a more digestible summary of that same data.

Can I download my mortgage results as a PDF?

Yes, use the “Download results as PDF” button below your results to save a summary of your inputs, monthly payment, total interest, total cost, and principal versus interest split, generated entirely in your browser.

Calculate your mortgage today

Your personalised mortgage payment estimate, total interest cost, and amortization schedule are calculated above, free and instant.

Calculate my mortgage ↑

Mortgage PaymentCalculator