How rate hikes or income drops affect your max affordable price
How to Use the Stresstest Calculator
Key Takeaways
Always run the 4% floor rate stress test — MAS assesses your TDSR at 4% regardless of the current market rate; this is the bank's actual approval threshold, not a hypothetical.
A 30% income drop stress test is more useful than a rate rise test for most salaried buyers — job loss is a more likely scenario than rates jumping 3% in a single year.
If the stress test shows your max affordable price drops below your target at 4% rate or 20% income drop, you are at the limit of serviceability — do not proceed without a buffer.
TDSR is 55% for private property, 30% MSR for HDB — switching property type dramatically changes your max affordable price at the same income.
The stress test result is the maximum the bank will approve; your comfortable purchase limit should be 10–15% below that to leave room for life changes.
What It Does
How would a rate hike or a pay cut change what you can afford? This calculator stress-tests your maximum affordable property price across two dimensions at once — interest rate increases (in 0.5% steps) and income reductions (in 10% steps) — using the same TDSR framework banks apply. The heatmap shows your maximum price at every combination, so you can see exactly where affordability breaks before committing to a purchase.
You can find this calculator in the Calculators tab on ShiokNest. It updates results instantly as you adjust inputs — no waiting, no page reloads.
Why It Matters
Banks approve loans against today's numbers, but you repay against tomorrow's. Singapore saw SORA-linked rates climb from under 1% to over 4% between 2021 and 2023 — a swing large enough to cut a buyer's maximum affordable price by six figures. Stress-testing before you commit shows whether your purchase survives a rate cycle or an income shock. This calculator matters because:
How It Works
Navigate to Calculators — Click the "Calculators" tab in the ShiokNest navigation bar. All calculators are grouped by purpose for easy access.
Select the calculator — Choose "Affordability Stress Test" from the calculator list. You will see default values already loaded so you can explore immediately.
Review the results — The calculator updates instantly as you change any input. The heatmap shows your maximum affordable price at each combination of rate increase and income drop, so weak spots stand out at a glance.
Run what-if scenarios — This is where the real power lies. Change one variable at a time to see its impact. For example, try increasing the interest rate by 1% or extending your holding period by 5 years. Note how the results shift.
Compare and decide — Run 2-3 different scenarios and note the results. This gives you a range of outcomes to base your decision on, rather than relying on a single projection.
Examples
$10K income buyer: how a 2% rate rise shrinks max affordable price
Inputs
Monthly income
$10,000 (gross)
Existing obligations
$0
Base rate
3.5% p.a. | Stress rate: 5.5% (+2%)
Loan tenure
25 years | Down payment: 25%
Property type
Private (TDSR 55%)
Results
Max monthly payment (TDSR)
$5,500
Max loan at 3.5%
~$1,069,000
Max loan at 5.5% (+2%)
~$875,000
Max affordable price drop
$1,425,000 → $1,167,000 (−$258,000)
How to read this:
At 3.5%, a $10K income buyer can afford a $1.43M property (75% LTV loan of $1.07M). If rates rise to 5.5% — which Singapore saw in the 2022–2023 cycle — the same income only supports a $1.17M property. That is a $258K reduction in purchase power for the same income and down payment. The stress test makes this scenario concrete before you commit. If you are buying today at 3.5% but rates could reach 5.5% in 18 months, you should stress-test your serviceability at the higher rate before s...
Income shock: 30% income drop — can you still service the mortgage?
Inputs
Monthly income
$12,000 (base) → $8,400 after 30% drop
Current rate
3.5% p.a.
Planned purchase
$1.6M condo (75% LTV = $1.2M loan)
Monthly mortgage at 3.5%, 25yr
$5,993/month
Results
TDSR at full income ($12K)
49.9% — within the 55% cap
TDSR at reduced income ($8,400)
71.3% — exceeds 55% cap by 16%
Monthly shortfall after income drop
$597/month above comfortable ceiling
Verdict
Current purchase is not survivable at 30% income drop
How to read this:
At full income, this buyer is within TDSR (49.9% vs 55% cap) and the bank will approve the loan. But a 30% income drop — realistic for contract workers, commission-based earners, or anyone facing retrenchment — pushes TDSR to 71.3%. That is 16% above the hard limit. The buyer has no buffer. The stress test recommends either reducing the purchase price to $1.3M (TDSR survives at 58.2% at reduced income, still too high) or targeting $1.1M (TDSR drops to 51% at reduced income — survivable)...
Tips & Pitfalls
Expert Tips
Use realistic assumptions — Singapore condo appreciation has historically averaged 2-4% per year. Avoid overly optimistic projections. When in doubt, use 3% as a baseline.
Be honest about opportunity cost — The down payment locked in your property could earn 5-7% in a diversified portfolio. The calculator factors this in.
Project rental increases — Singapore rents can rise 3-5% annually. If you rent long-term, this compounds significantly.
Common Pitfalls
Emotional bias — Most people have a strong emotional preference for owning. Let the numbers guide you, not the feeling.
Assuming appreciation is guaranteed — Property prices can stagnate or even dip for years. Test with 0% and 2% appreciation to see if buying still makes sense.
Frequently Asked Questions
Is my data saved?
No. All calculations run entirely in your browser. Nothing is stored on our servers or shared with third parties.
What is the MAS stress-test rate for mortgages?
MAS requires banks to assess private property TDSR at a minimum floor rate of 4%, regardless of the actual market rate. For HDB loans, the floor is 3.5%. This means even if you secure a 3% SORA-linked rate, the bank checks affordability as if the rate were 4%. The calculator defaults to 4% for this reason — it mirrors the actual bank assessment, not the current market rate.
Can I save my results?
Log in to save scenarios to your dashboard, or use the share button to copy a URL that encodes your inputs.
Does TDSR include all my debts?
Yes. TDSR (Total Debt Servicing Ratio) includes all monthly debt obligations: the new mortgage, any existing home loans, car loans, student loans, personal loans, and minimum credit card payments (typically 3% of outstanding balance). Enter all existing monthly obligations in the "Existing Obligations" field to get an accurate TDSR calculation. Missing obligations will overstate your borrowing capacity.
What is the difference between TDSR and MSR?
TDSR (55% cap) applies to all property loans — private condos, HDB, commercial. MSR (30% cap) is an additional constraint that applies specifically to HDB flat purchases and Executive Condominiums within MOP. MSR is more restrictive — for the same income, it allows a significantly smaller loan. For a $10K gross monthly income, TDSR allows up to $5,500/month in total debt payments; MSR limits the HDB loan payment alone to $3,000/month.