What is GST?
Goods and Services Tax is India’s destination-based tax on most goods and services. Registered businesses charge GST on taxable sales and show it clearly on invoices.
GST Calculator India
Free GST calculator online — exclusive or inclusive amounts with CGST, SGST, or IGST. Instant results, no sign-up.
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Instant
No signup
GST Calculator
FreeInvoiceOnline.com
Amount mode
Supply type
GST rate
Up to 4 decimal places · 0–100
Enter digits only · Indian format in results
Try an example
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How GST works
Last updated: July 2026
When to use IGST?
Use IGST for inter-state supply — when the supplier and the recipient are in different Indian states or Union Territories. The full rate is charged as a single IGST line.
When to use CGST + SGST?
Use CGST and SGST for intra-state supply — both parties in the same state. The GST rate is split equally between CGST and SGST (for example 9% + 9% at 18%).
Inclusive vs Exclusive
Exclusive: price before tax; GST is added. Inclusive: quoted price already contains GST; the calculator separates taxable value from tax. Switching modes keeps your entered amount and recalculates results.
Common GST rate slabs
| Rate | Typical use (examples) |
|---|---|
| 0% | Exempt / nil-rated supplies |
| 5% | Essential goods and some transport services |
| 12% | Processed foods and selected goods |
| 18% | Most services and many manufactured goods |
| 28% | Luxury and demerit goods (plus cess where applicable) |
Examples only — not legal advice. Confirm the applicable HSN/SAC rate for your goods or services.
Frequently Asked Questions
Which GST rates are supported?
The calculator includes the common India GST slabs — 0%, 5%, 12%, 18%, and 28% — plus a custom rate field for decimal percentages (for example 18.5% or 7.25%). Rates must be between 0 and 100 with up to four decimal places.
Can I calculate IGST as well as CGST and SGST?
Yes. Choose Intra-state (CGST + SGST) when the supplier and recipient are in the same state, or Inter-state (IGST) when they are in different states. The tax amount is the same; only the split differs.
What is the difference between exclusive and inclusive GST?
Exclusive GST means your amount is the taxable value and GST is added on top. Inclusive GST means your amount already includes tax, so the calculator backs out the taxable value and the GST portion.
Can businesses use this GST calculator?
Yes. Freelancers, consultants, and small businesses use it to estimate CGST, SGST, or IGST before creating a GST invoice or quotation. Figures are educational estimates — confirm final amounts with your accountant or the GST portal when filing.
Does this calculator support decimal GST rates?
Yes. Enter a custom rate with up to four decimal places. Currency results are always shown rounded to two decimal places for consistency with invoices.
Ready to create a GST invoice?
Turn your numbers into a professional PDF with CGST/SGST or IGST — free, no sign-up for standard templates.
This calculator provides educational estimates only and is not tax advice. Verify amounts with a qualified professional or the GST portal before filing.