Run the numbers first. Nothing is gated.
No email, no form, no “unlock your result”. Five tools computed by the same unit-tested engine that backs the public API, from rates checked against IRAS, MAS, HDB and CPF Board on 2026-08-01.
Everything runs in your browser. Nothing you type is sent or stored.
Rates verified 2026-08-01 · 14 statutory facts, each sourced
IRAS
01 / 05
Buyer’s, Additional Buyer’s and Seller’s Stamp Duty
The full duty bill on a purchase, band by band, at your residency and property count — plus the Seller’s Stamp Duty exposure that catches people who exit inside four years.
Seller's Stamp Duty applies within four years for residential property acquired on or after 4 July 2025. Earlier acquisitions use a three-year window.
Indicative only, based on published rates as at 2026-08-01. Verify with IRAS before committing. Not financial or legal advice.
- Buyer's Stamp Duty
- $44,600
- Additional Buyer's Stamp Duty
- $0
- Total stamp duty
- $44,600
- Down payment at max LTV
- $375,000
- — minimum in cash
- $75,000
- Total upfront capital
- $419,600
- Seller's Stamp Duty if sold now (8%)
- $120,000
You will get a straight answer, including “do nothing” where that is the right one.
MAS
02 / 05
Affordability and the MAS stress test
Total Debt Servicing Ratio at 55% and Mortgage Servicing Ratio at 30%, computed against the 4% medium-term rate floor rather than the rate you are quoted. It names which constraint actually binds — loan-to-value, TDSR or MSR — because that decides what to fix.
Interactive model
Stress-test the decision before you commit to it
Banks do not underwrite at the rate you are quoted. They underwrite at the MAS medium-term floor of 4% — which is why approved quantum and advertised affordability rarely agree. Model it here first.
Stress-tested at 4.0% regardless.
Indicative estimates only, based on published rules as at 2026-08-01. Stamp duty rates must be verified with IRAS and financing limits with MAS. This is not financial or legal advice, and it is not a loan approval.
Clears the stress test
LTV cap (75%) — you have income headroom but need more equity.
- Maximum loan
- $1,350,000
- Cash + CPF down payment
- $450,000
- — of which minimum cash
- $90,000
- Buyer's Stamp Duty
- $59,600
- Additional Buyer's Stamp Duty
- $0
- Total upfront capital required
- $509,600
- TDSR utilisation (cap 55%)
- 46.3%
- Highest price you clear
- $2,190,000
Opens WhatsApp with your figures pre-filled. Nothing is stored on this page.
You will get a straight answer, including “do nothing” where that is the right one.
IRAS · Stamp Duties Act
03 / 05
Decoupling: does the arithmetic work?
Buyer’s Stamp Duty on the transferred share, the CPF refund with accrued interest and refinancing, set against the ABSD it is meant to save. Frequently the answer is that it does not work — and this is where you find that out, not afterwards.
Under four years may trigger Seller's Stamp Duty on the transferred share.
Assumes both parties are Singapore Citizens and the remaining owner can independently service the existing loan under TDSR — the condition that most often fails in practice. Indicative only, rates as at 2026-08-01. Verify with IRAS. Not financial or legal advice.
Ahead by $333,400
On these inputs the ABSD avoided exceeds the cost of executing the transfer. The remaining question is whether the surviving owner clears TDSR on the existing loan alone.
- Value of transferred share
- $700,000
- BSD on the transfer
- $15,600
- SSD on the transfer
- $0
- Legal + refinancing
- $11,000
- Total cost to decouple
- $26,600
- ABSD avoided on next purchase
- $360,000
- Net position
- +$333,400
You will get a straight answer, including “do nothing” where that is the right one.
IRAS · market
04 / 05
Net rental yield
Gross yield is the number in the advertisement. This one takes off property tax at non-owner-occupier rates, agency commission, maintenance and a vacancy allowance.
Non-owner-occupied rates are materially higher. Check your IRAS notice.
Aircon servicing, appliances, touch-ups between tenancies.
Be honest. Zero is not a plan.
Financing (set loan to 0 if unencumbered)
Indicative only, as at 2026-08-01. Property tax rates must be verified with IRAS. Excludes income tax on net rental income. Not financial or tax advice.
$6,968/yr shortfall
Gross yield says 3.86%. Net yield is 2.41% — a 1.45 point gap once tax, maintenance, commission and vacancy are priced in. The listing quotes the first number. You live on the second.
- Gross annual rent
- $54,000
- Effective rent (11 months let)
- $49,500
- Total annual costs
- $15,813
- Net income before mortgage
- $33,688
- Gross yield
- 3.86%
- Net yield
- 2.41%
- Annual mortgage
- $40,656
- Cashflow after mortgage
- -$6,968
- Break-even occupancy
- 29%
You will get a straight answer, including “do nothing” where that is the right one.
MOE · OneMap
05 / 05
Primary school proximity
Which primary schools sit within the 1km and 2km bands of an address, and — more usefully — the registration priority order that actually decides admission.
Primary One planning
Which primary schools is this address near?
Enter a six-digit postal code, or a block and street name. The result is a straight-line estimate against the MOE-published 1km and 2km bands — read the caveat below before you let it influence an offer.
How admission is actually decided, and the limits of this tool
The order that decides admission
- 1Singapore Citizens living within 1km of the school
- 2Singapore Citizens living between 1km and 2km
- 3Singapore Citizens living outside 2km
- 4Permanent Residents living within 1km
- 5Permanent Residents living between 1km and 2km
- 6Permanent Residents living outside 2km
Every Singapore Citizen is processed before any Permanent Resident, regardless of distance. A citizen living outside 2km ranks ahead of a PR living 200 metres away.
A child admitted on distance priority must live at the registered address for at least 30 months. MOE states that where this is not met it will transfer the child to a school of its sole discretion, with no parental choice.
Indicative only — not an official MOE measurement. Distances shown are straight-line estimates between approximate coordinates. MOE calculates Home-School Distance as the shortest distance from any point on the school's land boundary to your home's building outline, using its own GIS data — a method that typically returns a shorter distance than the figure shown here. Properties near a 1km or 2km threshold may fall in a different band under MOE. Always verify with the official OneMap School Query tool and MOE before making any property decision. Distance confers priority within a balloted pool; it never guarantees a place.
Contains information from the General information of schools dataset accessed from data.gov.sg and geocoded via OneMap (Singapore Land Authority), made available under the terms of the Singapore Open Data Licence version 1.0.
You will get a straight answer, including “do nothing” where that is the right one.
For developers and AI agents
The same engine, callable
These are not screen-only widgets. The arithmetic behind them is a pure, unit-tested module exposed over a public JSON API with an OpenAPI 3.1 descriptor, and as a Model Context Protocol server so an AI agent can call it as a tool. No key, no rate-limit negotiation, and every response cites the authority it came from.
Calculators
What people ask about these tools
Are these calculators free, and do I have to give my email?
Free, and no. Every tool on this page runs entirely in your browser. The figures you type are not transmitted anywhere and are not recorded. They leave your device only if you choose to send them by WhatsApp, which you do yourself.
How current are the rates behind them?
The engine reads from a registry of 14 statutory rates, each carrying its issuing authority, its effective date and a link to the source page. That registry was last checked against the authorities on 2026-08-01 — and that date is published rather than hidden, because a property calculator with undated rates is a liability.
Why does the affordability tool use 4% when my bank quoted me less?
Because your bank has to. MAS requires the debt servicing ratios to be computed against a medium-term interest rate floor of 4% for residential property, not the promotional rate on the offer. A calculator using the quoted rate will tell you that you qualify for a loan you will not be granted.
Can I use these numbers to make an offer?
Use them to rule options in and out. Before you commit, confirm the stamp duty position with IRAS and the loan with the bank in writing — an in-principle approval is indicative until it is not. These tools are general information, not advice on your circumstances.
Is there an API?
Yes. The same engine is exposed at https://joelgoh.co/api/v1 with an OpenAPI 3.1 descriptor, and as a Model Context Protocol server for AI agents. No authentication, and every response carries citations back to the issuing authority.
Results are general information computed from published rates on the verification date shown, not advice on your circumstances.