GST / VAT Calculator

GST/VAT Calculator — Owner’s Guide

Friendly, non-technical instructions for shop owners and staff to calculate GST/VAT, see tax breakdowns, and compute tax-inclusive or tax-exclusive prices right from your dashboard.


What this tool does

  • Calculate tax-inclusive price from a base price (price before tax).

  • Calculate tax-exclusive base from a tax-inclusive price (extract tax).

  • Show a clear tax breakdown (tax amount, final price).

  • Support common VAT/GST workflows including split of GST into CGST + SGST (domestic) or IGST (interstate), and generic VAT where applicable.

  • Useful for pricing, receipts, quoting, and reconciling cash register totals.


Who should use it

  • Shop owners, managers, cashiers, accountants and anyone preparing bills or price lists.

  • No developer knowledge required — simple form input and instant results.


Where to find it

Dashboard → GST/VAT Calculator (accessible per place/shop).


How to use — quick steps

1) Choose calculation mode

  • Add tax to base price (Tax Exclusive → Tax Inclusive) — enter base price and tax rate to get final price.

  • Remove tax from total price (Tax Inclusive → Tax Exclusive) — enter total paid price and tax rate to find tax amount and base price.

2) Enter values

  • Price: numeric (e.g., 1000, 99.99)

  • Tax rate: percentage (e.g., 18 for 18%)

  • Tax type: choose GST (then choose how to split) or VAT (single tax).

3) View results

  • You’ll see:

    • Base price (tax-exclusive)

    • Tax amount

    • Final price (tax-inclusive)

    • If GST selected, a split (CGST/SGST each = half of GST rate) or IGST shown as single

4) Use outputs

  • Copy numbers into invoices, POS, price tags, or stock pricing updates.


Formulas (simple, copyable)

  • Add tax (tax-exclusive → tax-inclusive) Final price = Base price × (1 + tax_rate / 100)

    Example: Base 100, tax 18% → 100 × 1.18 = 118

  • Extract tax (tax-inclusive → tax-exclusive) Base price = Final price ÷ (1 + tax_rate / 100) Tax amount = Final price − Base price

    Example: Final 118, tax 18% → 118 ÷ 1.18 = 100 → Tax = 18

  • Split GST into CGST & SGST (when applicable domestically) CGST = SGST = Tax amount ÷ 2 Or split rate: each = tax_rate ÷ 2

    Example: GST 18% → CGST 9%, SGST 9% → For base 100: CGST = 9, SGST = 9


Examples (real situations)

  1. You buy a product at ₹500, GST 12% — what will you charge including tax? Final = 500 × 1.12 = ₹560 (Tax = ₹60 → CGST ₹30 + SGST ₹30)

  2. Customer paid ₹224 (tax-inclusive) and GST is 12% — what's the base price? Base = 224 ÷ 1.12 = ₹200 → Tax = ₹24 (CGST ₹12 + SGST ₹12)

  3. VAT 20% on an item priced £120 (tax-inclusive) Base = 120 ÷ 1.20 = £100 → VAT = £20


Common use-cases for shops

  • Price tags: set tax-inclusive shelf price quickly.

  • Invoices & receipts: verify tax split before printing or emailing.

  • Quoting customers: present both tax-exclusive and tax-inclusive prices.

  • Accounting: reconcile cash vs expected tax collected.


Tips & best practices

  • Always confirm tax type (GST vs VAT) and whether the sale is intra-state (CGST+SGST) or inter-state (IGST) before splitting.

  • Round only at final step — do calculations to enough precision (2 decimal places for currency) and round the final amounts to avoid tiny rounding errors.

  • Save frequently used rates (e.g., 5%, 12%, 18%, 28%) in your calculator if available to speed up entry.

  • For bundled items, calculate tax per line item where possible and then sum — that reduces discrepancies on invoices.


Notes about CGST / SGST / IGST (GST systems)

  • If both buyer and seller are in the same state: GST is split into CGST + SGST (equal halves).

  • If buyer and seller are in different states: IGST applies (full GST rate as single tax).

  • The calculator can show the split but does not replace legal tax advice — follow local tax rules for filing.


Edge cases & validation

  • Zero tax rate: calculator will return final price = base price (no tax).

  • Negative or zero price: not valid — use refunds or credit notes workflows instead.

  • Very large tax rates or invalid inputs: you’ll get an error prompt — re-check entries.


Quick Reference / Cheat Sheet

  • Add tax: Final = Base × (1 + R/100)

  • Remove tax: Base = Final ÷ (1 + R/100)

  • Tax amount (from base): Base × (R/100)

  • For GST split: CGST = SGST = Tax amount ÷ 2


Troubleshooting & FAQ

Q: Why doesn’t the tax split match my invoice? A: Check whether the invoice used per-item rounding or per-invoice rounding. Small rounding differences may appear if rounding happens at line-item level.

Q: Can I set default tax rates for my shop? A: If your dashboard supports it, set common tax rates in shop settings so the calculator populates them by default.

Q: Does this handle discounts or multiple tax rates? A: The calculator handles one tax rate at a time. For discounts, apply the discount to the base price first, then compute tax. For items with different tax rates, calculate separately per item.

Last updated