18% Tax on $30
Tax amount, total price, step-by-step formula, and regional context.
Tax Amount
$5.40
Total Price
$35.40
Effective Rate
15.2542%
$30 × 1.18 = $35.40
Formulas
Add tax (total):
Price × (1 + Rate/100)
Tax amount only:
Price × Rate/100
Remove tax (pre-tax):
Total ÷ (1 + Rate/100)
Effective rate:
(Tax ÷ Total) × 100
Step-by-Step
1
Convert to decimal
18 ÷ 100 = 0.18
2
Calculate tax
$30 × 0.18 = $5.40
3
Add to price
$30 + $5.40 = $35.40
4
Verify (reverse)
$35.40 ÷ 1.18 = $30 ✓
Pre-tax
$30
Tax added
$5.40
Total
$35.40
Eff. rate
15.2542%
Reverse: Remove 18% from $35.40
If you have a tax-inclusive total of $35.40 and need to extract the 18% tax:
$35.40 ÷ 1.18 = $25.42 pre-tax
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Where is 18% used? — India GST (standard)
India's standard GST rate applied to most services and many goods.
Real-World Context
A $30 purchase with 18% tax costs $35.4 all-in. The $5.4 is what the retailer collects and remits — it doesn't stay with the seller.
Frequently Asked Questions
How much is 18% tax on $30?
18% tax on $30 is $5.40. Total including tax: $35.40. Formula: $30 × 0.18 = $5.40, then $30 + $5.40 = $35.40.
How do I remove 18% tax from $35.40?
Divide by 1.18: $35.40 ÷ 1.18 = $25.42 pre-tax. Tax component: $9.98.
Why is the effective rate (15.2542%) lower than 18%?
The 18% rate applies to the pre-tax amount ($30). The effective rate — tax as a share of the total ($35.40) — is always lower because the denominator is larger.
Where is 18% tax used?
India GST (standard): India's standard GST rate applied to most services and many goods. Always verify the current rate with your local tax authority.
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