GST Calculator
A GST calculator is a free online tool that computes Goods and Services Tax for any amount β either adding GST to a base price or extracting it from an inclusive price.
How to use GST Calculator
- Enter amount β Type the base amount or the GST-inclusive amount.
- Choose GST rate β Select 5%, 12%, 18%, or 28% β or enter a custom rate.
- Choose mode β Add GST (exclusive) or remove GST (inclusive).
- See breakdown β View base amount, GST amount, CGST, SGST, and total.
Key features
- Add or remove GST instantly
- CGST/SGST/IGST split shown
- All standard Indian GST rates
- Custom rate support
- No signup, 100% private
What is GST?
Goods and Services Tax (GST) is India's comprehensive indirect tax on the supply of goods and services. Introduced on July 1, 2017, it replaced a complex web of central and state taxes with a single unified tax. GST applies at every stage of the supply chain, but is ultimately borne by the end consumer. For businesses, GST compliance means monthly or quarterly filing and accurate invoicing.
The GST Rate Slabs
India uses a multi-tier GST structure. Essential goods fall under 0% or 5%. Standard goods and most services fall under 12% or 18%. Luxury and sin goods fall under 28%, often with additional cess. Getting the rate right is critical β using the wrong rate can result in penalties during GST audits.
CGST, SGST, and IGST Explained
For sales within the same state, GST is split equally into CGST (Central GST) and SGST (State GST). For inter-state sales, a single IGST (Integrated GST) is charged, which the central government distributes to the destination state. This tool automatically shows the correct split for intra-state transactions.
Why Use Our GST Calculator?
Our calculator is designed for Indian businesses β freelancers, shop owners, consultants, and e-commerce sellers. It works instantly, requires no signup, and shows the complete breakdown: base amount, GST, CGST, SGST, and total. For full GST invoicing, generate a professional invoice with ShopBill Pro's flagship software.
Pro tips
- Always verify GST rate based on HSN/SAC code for your product
- For inter-state sales, use IGST instead of CGST+SGST
- Round GST amounts to nearest rupee in invoices per GST rules
- Save calculation screenshots for your accountant
Common use cases
- Calculating GST for invoices and bills
- Filing monthly GST returns (GSTR-1, GSTR-3B)
- Pricing products with correct tax
- Reverse-calculating base price from inclusive amount
- Freelancers billing clients
Frequently asked questions
What is GST?+
GST (Goods and Services Tax) is India's unified indirect tax that replaced multiple taxes like VAT, service tax, and excise duty in 2017.
What are the GST rates in India?+
Common rates are 0%, 5%, 12%, 18%, and 28%. Most services fall under 18%.
What is the difference between CGST, SGST, and IGST?+
CGST (Central GST) and SGST (State GST) apply to sales within a state. IGST (Integrated GST) applies to inter-state sales.
How do I calculate GST?+
For exclusive: GST = base Γ rate / 100. For inclusive: base = total / (1 + rate / 100).
Is this calculator free?+
Yes, 100% free with unlimited usage.
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