GST Calculator – Add or Remove Tax

A GST calculator adds or removes Goods and Services Tax from any price. Adding multiplies the net price by the rate; removing backs the tax out of a tax-inclusive total instead of guessing. The computation rests on GST = net × rate ÷ 100 | Net from gross = gross × 100 ÷ (100 + rate). On a net 1,200 invoice at 5%, GST is 1,200 × 0.05 = 60 and the gross total 1,260; from a gross 1,260 the net is 1,260 × 100/105 = 1,200 and the tax 60. Each input you type is substituted the instant you release the key, and the result is expressed in exactly the units or currency you chose.

1. 1

   Step 1

   Start with the primary figures the GST Calculator asks for.

2. 2

   Step 2

   Your values are substituted into GST = net × rate ÷ 100 | Net from gross = gross × 100 ÷ (100 + rate).

3. 3

   Step 3

   Read off the computed result.

4. 4

   Step 4

   Vary one input at a time to see its effect.

• Subtracting instead of dividing

• Mixing rate bases

• Ignoring GST-inclusive quotes