GST Calculator
Add GST to a base price or work out the GST already inside a total. Choose intra-state supply to see the CGST/SGST split, or inter-state supply to see IGST, for any Indian GST slab.
How to use gst calculator
- Choose a mode and supply type
Add GST to a base price or remove it from a GST-inclusive total; pick intra-state or inter-state supply.
- Pick the rate
Select a standard slab (3/5/12/18/28%) or enter a custom rate.
- Calculate
Enter the amount and click Calculate to see the full breakdown.
Features
Handle both 'add GST' and 'GST already included' scenarios.
Switch between intra-state billing (CGST + SGST split) and inter-state billing (single IGST line), matching how real invoices are taxed.
Supports 3%, 5%, 12%, 18%, 28% and a custom rate.
Supported formats and limitations
Text and structured input supported by this tool.
Use cases include personal workflows, content preparation, and quick checks. Review output before relying on it for legal, financial, accessibility, or production decisions.
Frequently asked questions
How is GST removed from an inclusive price?
Base = total × 100 ÷ (100 + rate). The GST is the difference between the total and that base amount.
What are CGST and SGST, and when is IGST used instead?
For a sale within the same state, GST is split equally into Central GST and State GST. For a sale between two different states, the seller charges Integrated GST (IGST) instead — a single line equal to the full GST amount, not split. Choose the matching supply type above to see the correct breakdown.
Can I use a non-standard rate?
Yes — choose Custom and type any percentage for special cases. 3% is included as a preset because it's the standard rate on gold, silver and jewellery.