Free Percentage, Discount & GST Calculator Online

GST / Sales Tax Calculator

Amount ($ / Rs / €)

Tax Rate (%)

Calculation Mode

Net Amount

1000.00

Tax Amount

180.00

Gross Total

1180.00

Quick Percentage Formulas

1. What is X% of Y?

= 37.50

2. X is what percent of Y? (Marks %)

= 76.36%

3. Percentage Change from X to Y

+30.00%

How to Calculate Percentages, Discounts & GST Accurately

Whether you are calculating inclusive or exclusive GST for a client bill on our Free Invoice Generator, checking retail discounts, or working out exam marks percentages, our online percentage calculator delivers instant results without manual formula errors.

Core Percentage & Tax Formulas

Exclusive Tax: Tax = (Net Price × Tax Rate) / 100.
Inclusive Tax Extraction: Net Price = Total Price / (1 + (Tax Rate / 100)).
Exam Marks Percentage: (Obtained Marks / Total Marks) × 100.

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