Remove GST Calculator (Reverse GST)

Works backwards from a GST-inclusive price to show how much of it is GST.

Result

GST included
S$9.00
Price before GST
S$100.00

How to use the remove gst calculator (reverse gst)

  1. Enter the price including gst (S$).
  2. The results update as you type, or press Calculate.
  3. Read the gst included first, then the supporting figures below it.

Formula

GST portion = inclusive price × 9/109.

Worked example

For example, with these inputs:

the calculator returns:

Background

Reliefs lower chargeable income before rates apply. Common ones include earned income relief, CPF relief for employee contributions, parent and handicapped parent relief, working mother's child relief, NSman relief, course fees relief, and relief for SRS contributions and CPF cash top-ups. Total personal reliefs are capped at S$80,000 a year.

Tax planning in Singapore is mostly about timing and reliefs rather than complex structures. Topping up CPF, contributing to SRS and claiming every relief you qualify for can lower your marginal rate band, and the savings are larger for higher earners.

Frequently asked questions

How does the remove gst calculator (reverse gst) work?

It applies this formula: GST portion = inclusive price × 9/109.

Is this the same as my IRAS bill?

It is an estimate based on the published rates. Your notice of assessment will reflect all reliefs, rebates and income IRAS holds for you.

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