GST Calculator

The Goods and Services Tax (GST) is a broad-based value-added consumption tax levied on the import of goods, low-value cross-border supplies, and almost all supplies of goods and services in Singapore. Enforced by the Inland Revenue Authority of Singapore (IRAS) under the Goods and Services Tax Act 1993, the statutory GST rate stands at 9% (effective from January 1, 2024 onwards).

GST is designed as a multi-stage tax collected at every step of the economic distribution chain. Registered businesses act as collecting agents for the Singapore Government:

• Output Tax: The 9% GST that registered businesses charge and collect from customers on standard-rated supplies.
• Input Tax: The 9% GST that registered businesses pay to suppliers on their own business purchases and operating expenses.
• Net GST Settled: Every quarter, businesses file Form F5 on myTax Portal, paying IRAS the difference (Output Tax minus Input Tax) or claiming a tax refund if Input Tax exceeds Output Tax.

While standard local supplies incur 9% GST, exported goods and international services qualify for zero-rating (0% GST), allowing exporters to reclaim all incurred input taxes. Essential domestic financial services, digital payment tokens, and the sale and lease of residential properties are treated as exempt supplies outside the GST scope. To master compliance, explore our comprehensive Singapore 9% GST Rate Guide, inspect import rules in our E-Commerce & Low-Value Goods GST Guide, check airport claims in our Tourist GST Refund (eTRS) Guide, and review corporate filings in our Singapore Corporate Tax Guide.

Compute exact 9% GST components, net pre-tax amounts, and total gross customer invoices in Singapore Dollars (SGD / S$):

1. Enter Transaction Amount: Type your monetary transaction figure in Singapore Dollars (e.g. 100, 1000, 5000).
2. Select GST Rate: Choose 9% - Standard GST (2024+) or 0% - GST Exempt / Zero-Rated for exports.
3. Select Calculation Mode:
   • Add GST (GST Exclusive): Use this when you have a net base price and need to add 9% tax (e.g. S$1,000 becomes S$1,090).
   • Remove GST (GST Inclusive): Use this when you have a gross retail price (such as a restaurant bill or store receipt) and need to extract the embedded 9% tax using the 9/109 statutory formula.
4. Click Calculate: Instantly view itemized GST Amount, Total Gross Amount, and Net Base Amount.
5. Export or Copy: Copy figures directly into your corporate bookkeeping ledger, quotation template, or quarterly IRAS Form F5 return.

The calculation output isolates each financial metric for accounting and invoicing transparency:

Price Display Regulation: Under IRAS price display regulations, all GST-registered retail businesses displaying prices to the general public (e.g. in stores, menus, or websites) must quote GST-inclusive prices upfront to prevent deceptive pricing.

To compute GST accurately without rounding discrepancies, IRAS specifies two official mathematical standards:

To illustrate how the 9% GST rate applies across different transaction formats in Singapore, consider three typical use cases:

• Full 9% Statutory Alignment: Calibrated strictly to current Singapore IRAS tax schedules (2024 to 2026).
• Dual Inclusive/Exclusive Functionality: Instant conversion between retail shelf prices and B2B commercial quotes.
• Exact Fractional Accuracy: Applies the official 9/109 IRAS extraction fraction to eliminate rounding discrepancies.
• Connected Singapore Tax Ecosystem: Seamlessly linked to our 9% GST Complete Guide, E-Commerce & LVG GST Guide, and Corporate Tax Guide.

• Partial Exemption Apportionment: Businesses making both taxable and exempt supplies must apply IRAS partial exemption input tax apportionment formulas.
• Pre-Registration Input Tax: Reclaiming input tax on goods and services acquired prior to GST registration is subject to special 6-month and asset usage rules.
• Major Exporter Scheme (MES): Companies under MES enjoy suspension of import GST at Singapore customs, which requires specialized customs documentation.

Understanding the statutory GST framework enforced by IRAS in Singapore:

• Missing the S$1 Million Compulsory Registration Threshold: Businesses must monitor taxable turnover on a retrospective basis (at the end of each calendar year) and on a prospective basis (if turnover in next 12 months is expected to exceed S$1M). Late registration incurs backdated tax liabilities and penalties of up to 10% under Section 71.
• Extracting GST Using 9% Instead of 9/109: When calculating GST on a gross inclusive price of S$100, multiplying by 0.09 yields S$9.00 (which is mathematically incorrect). The true embedded tax is 100 × (9 / 109) = S$8.26. Using 0.09 leads to accounting errors and overpaying GST to IRAS!
• Claiming Input Tax on Blocked Expenses: Under Regulation 26 of the GST (General) Regulations, input tax is strictly blocked from claims on club subscription fees, medical insurance for family members, family benefits, and motor car expenses (petrol, maintenance, COE, and rental for passenger cars).
• Failing to Maintain Proper Tax Invoices: You cannot claim input tax using general credit card slips or non-tax receipts. A full tax invoice stating the supplier's GST registration number and word "Tax Invoice" is mandatory for purchases exceeding S$1,000.
• Violating Price Display Guidelines: Quoting prices to retail customers as "S$100 + GST" is an offence under Section 75. Retail customer prices must be quoted inclusive of 9% GST.

• Inland Revenue Authority of Singapore (IRAS) — Official GST Guides, e-Tax Guides & Rate Schedules
• myTax Portal (IRAS) — Quarterly GST Return Filing (Form F5) & Electronic Registration
• Singapore Customs — Import GST Payments, Major Exporter Scheme (MES) & Port Clearance

GST-registered businesses must preserve all tax invoices, payment vouchers, and export bills of lading for 5 years under Section 46 of the GST Act.