Calculate GST Instantly
Add or remove GST, calculate tax-inclusive and tax-exclusive prices, and get an accurate CGST, SGST or IGST breakdown across multiple items — right in your browser.
Use the calculatorMulti GST Calculator (Add GST)
Enter one or more items below — the same fields work for a single amount or a full invoice.
What you can calculate
Everything this tool supports, nothing it doesn't.
Add GST
Get the total amount once GST is added to a base price.
Remove GST
Find the original base amount from a GST-inclusive price.
6 built-in rates
0%, 3%, 5%, 12%, 18%, 28% — plus a custom rate field.
Multiple items
Add rows for a full invoice, each with its own rate.
CGST + SGST
Automatic 50/50 split for intra-state supply.
IGST
Full-rate GST calculated for inter-state supply.
Your result
| Item | Taxable | Rate | GST | Total |
|---|
Total taxable amount
₹0.00
Total IGST
₹0.00
Total CGST
₹0.00
Total SGST
₹0.00
Total GST amount
₹0.00
Calculation methods & use cases
See how GST is worked out in different real-life situations, with formulas, examples and who typically uses each one.
Remove GST from a bill amount
Find the original amount from a GST-inclusive bill.
Use case
A civil work contractor receives a bill from a government project. The bill amount includes GST, and they need to find the base amount for their records.
Formula & example
Bill = ₹1,18,000 at 18% → ₹1,00,000 base
Who uses it
- Civil contractors
- Government contractors
- Accountants
- Billing teams
Applications
Government work bills, contract billing, invoice verification.
Add GST to a base amount
Calculate the total amount including GST.
Use case
A supplier knows their product's base price and wants to add GST to get the final amount to charge a customer.
Formula & example
Base = ₹50,000 at 18% → ₹59,000 total
Who uses it
- Business owners
- Retailers
- Freelancers
- Service providers
Applications
Creating invoices, quotations, pricing products or services.
Calculate only the GST amount
Find the GST amount from a total or base value.
Use case
You just need to know how much GST is charged on a particular bill or product, without the full total.
Formula & example
Base = ₹1,00,000 at 18% → ₹18,000 GST
Who uses it
- Traders
- Accountants
- Students
- Business owners
Applications
Tax reporting, invoice checking, financial planning.
Multiple items with different rates
Calculate GST for multiple products or services.
Use case
A business sells several products taxed at different slabs (5%, 12%, 18%) and wants one combined total for all items.
Formula & example
3 items (5%, 12%, 18%) → ₹8,300 GST total
Who uses it
- Retailers
- Distributors
- E-commerce sellers
- Inventory managers
Applications
Bulk invoicing, order billing, GST reports, stock management.
CGST and SGST breakdown
Get the central and state GST split for intra-state supply.
Use case
A sale happens within the same state, and the central and state GST components need to be shown separately.
Formula & example
₹18,000 GST → ₹9,000 + ₹9,000
Who uses it
- Local businesses
- Traders
- Manufacturers
- GST professionals
Applications
Intra-state sales, GST return filing, accounting, compliance.
IGST for inter-state supply
Calculate IGST for inter-state transactions.
Use case
Goods or services move to a different state, so the full GST rate applies as a single IGST amount instead of a split.
Formula & example
₹1,00,000 at 18% → ₹18,000 IGST
Who uses it
- Inter-state traders
- Exporters
- E-commerce sellers
- Logistics companies
Applications
Inter-state sales, export transactions, GST compliance, international trade.
One tool. Multiple GST solutions.
From simple calculations to complex scenarios, this GST calculator handles all your needs.
Clear, simple, transparent
What this GST calculator does, what it doesn't, and where its limits are — no fine print.
Tool limits
- Standard rates: 5%, 12%, 18%, 28%, or any custom rate you enter
- Multiple products or services calculated in one pass
- Works on desktop, tablet, and mobile with no install
- No usage limit — free every time
What this tool does
- Adds GST to a base amount to get the total
- Removes GST from a GST-inclusive amount
- Splits GST into CGST + SGST for intra-state supply
- Shows IGST for inter-state supply
What this tool does NOT do
- It isn't legal or financial advice — results are for calculation purposes only
- It doesn't account for industry-specific exemptions — verify with official GST rules
- It doesn't store anything — every calculation runs in your browser
- It doesn't generate compliant invoices or file returns
Helpful resources
One guide worth reading, and the official links worth bookmarking.
GST Calculation Guide
A complete guide to GST calculation
- Step-by-step explanations
- Formulas with worked examples
- Real-life use cases
Learn how to add, remove, and calculate GST with clear formulas and examples, plus a plain-language look at CGST, SGST and IGST.
Read the full guideEverything you need to know
Quick answers about how this calculator works, and what to do if something looks off.
Using the tool
What can I calculate with this GST Calculator?
You can add GST to a base amount, remove GST from an inclusive amount, and see a CGST+SGST or IGST split — across single or multiple items.
Which GST rates are supported?
0%, 3%, 5%, 12%, 18% and 28% are built in. Choose "Custom..." from the rate dropdown to enter any other percentage.
Can I calculate multiple items at once?
Yes. Click "+ Add another item" to add as many product or service rows as you need — each can carry its own rate.
Is my data stored anywhere?
No. Every calculation happens locally in your browser — nothing you enter is sent to or saved on a server.
Troubleshooting
Why isn't my result showing?
Make sure at least one item has a valid amount greater than zero and a valid rate — rows that don't are skipped when you click Calculate.
Why did my result change or disappear?
Editing any field after calculating marks the result as out of date, shown by the notice above the buttons. Click Calculate again to refresh it.
I entered a custom rate — why doesn't it apply?
Confirm the rate dropdown for that item is set to "Custom..." — the typed value is only used when that option is selected.
Are these results valid for tax filing?
No — treat them as estimates for planning. For return filing and compliance, confirm figures with a qualified tax professional.
Ready for your next calculation?
No signup, no limits — just accurate GST results whenever you need them.