GST Calculator
Calculate GST amounts, add or remove GST from prices, and compute CGST, SGST, and IGST splits.
Compute total price and tax components from a tax-exclusive base price and GST percentage rate.
Total price including 18% GST
How to Calculate GST (Goods and Services Tax)
Formulas for adding GST, removing GST from inclusive totals, and splitting intra-state and inter-state tax components.
1. Add GST Formula (Forward Calculation)
Multiply the pre-tax base price by the GST rate percentage and divide by 100 to compute the GST amount, then add it to the base price to find the total invoice amount.
When to use: Use when billing customers from a net catalog price or calculating tax on pre-tax quotes.
2. Remove GST Formula (Reverse Calculation)
Divide the gross inclusive price by (1 + GST% / 100) to extract the pre-tax base price, then subtract the base price from the inclusive price to obtain the exact GST amount.
When to use: Use when analyzing MRP retail bills or reverse-engineering pre-tax amounts from gross receipts.
3. Tax Component Split (CGST, SGST & IGST)
For intra-state transactions (within the same state), GST is split equally between Central GST (CGST) and State GST (SGST). For inter-state transactions, Integrated GST (IGST) applies to the full tax amount.
When to use: Use when preparing invoice tax summaries and determining tax liability across state boundaries.
Practical Calculation Examples
Real-world scenarios illustrating step-by-step numbers, inputs, and verified outputs.
Example 1: 10,000 with 18% GST (Intra-State)
Adding 18% GST to a base service fee of 10,000 within the same state.
Example 2: 11,800 Gross Amount at 18% GST (Remove GST)
Extracting the base price and tax amount from an 11,800 gross bill.
Example 3: 10,000 with 5% GST (Intra-State)
Calculating 5% essential goods GST on a 10,000 base purchase.
Example 4: 10,000 with 18% GST (Inter-State IGST)
Calculating inter-state supply tax with integrated IGST applied.
Frequently Asked Questions
Common questions about GST calculations, adding or removing tax, CGST, SGST, IGST splits, and invoice pricing.
How do I calculate GST using a calculator?
Enter your pre-tax base price and the applicable GST percentage rate into the calculator. The tool calculates total GST (Base Price × GST% ÷ 100) and displays both the tax amount and the gross total price.
How do I calculate 18% GST?
To add 18% GST, multiply the base price by 0.18 to find the tax amount, or by 1.18 to get the final inclusive total. To remove 18% GST from a gross amount, divide the gross inclusive price by 1.18 to find the pre-tax base price.
How do I calculate GST-inclusive and GST-exclusive prices?
To find a GST-inclusive price from an exclusive amount, use the 'Add GST' mode (Final Price = Base Price + Base Price × GST% ÷ 100). To extract an exclusive base price from an inclusive total, use the 'Remove GST' mode (Base Price = Inclusive Price ÷ (1 + GST% ÷ 100)).
What is the difference between CGST, SGST/UTGST and IGST?
In this calculator, Intra-State mode splits the entered GST rate equally between Central GST (CGST) and State/UT GST (SGST/UTGST). Inter-State mode applies the entered rate fully as Integrated GST (IGST). Actual GST treatment and classification depend on the specific transaction and prevailing tax rules.
How do I calculate the price before GST?
Use the Remove GST mode and enter the gross invoice amount and GST rate. The calculator divides the inclusive price by (1 + GST% ÷ 100) to find the pre-tax base price.
How do I add GST to an amount?
Enter the pre-tax amount and GST percentage in the 'Add GST' mode. The calculator multiplies the base price by the rate percentage and adds it to the base price to produce the final gross total.
Can I enter a custom or decimal GST rate?
Yes. YourCalculate supports standard GST slabs (0%, 5%, 12%, 18%, 28%) as well as custom or fractional rates (such as 0.25%, 3%, or 18.5%) with exact floating-point precision.
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