GST Calculator
Add or remove GST from any amount. Supports all Indian GST slabs.
What is the GST Calculator?
The GST Calculator computes Goods and Services Tax for any price — inclusive or exclusive of tax — at any GST rate (0%, 5%, 12%, 18%, 28%). Enter the amount and rate and the tool returns the tax component and the final invoice value with a full breakdown.
Getting GST right matters for retailers, freelancers and consumers. Whether you are issuing an invoice, checking a bill or setting a menu price, the calculator removes the mental arithmetic and prevents small errors that can compound into big compliance headaches.
The tool runs entirely in your browser — your invoice amounts, customer details and price lists are never uploaded.
How to use the GST Calculator
- 1Enter the base amount or the total amount.
- 2Choose whether that amount already includes GST or not.
- 3Pick the applicable GST rate (5%, 12%, 18%, 28% or custom).
- 4Read the CGST, SGST/IGST components and the final value.
- 5Copy or print the breakdown as needed.
Key features
- Add-GST and remove-GST modes
- Standard Indian slab rates plus custom rates
- CGST + SGST split for intrastate transactions
- IGST option for interstate
- Instant recalculation on every change
- Runs offline
Examples
Add GST
A base price of ₹1,000 at 18% GST becomes ₹1,180 (₹90 CGST + ₹90 SGST).
Remove GST
An MRP of ₹590 including 18% GST breaks down to ₹500 base + ₹90 GST.
Interstate sale
A ₹2,000 interstate invoice at 12% shows ₹240 IGST rather than a CGST/SGST split.
Why use this tool
- Eliminates GST calculation errors
- Speeds up invoice creation
- Handles both add and remove scenarios
- Works for any GST rate you enter
- Data stays private
Common use cases
- Creating invoices as a freelancer
- Checking bills at restaurants and shops
- Pricing products for a retail catalogue
- Reconciling accounting entries
- Teaching students how GST works
Frequently asked questions
What are the standard GST rates in India?
0%, 5%, 12%, 18% and 28% are the main slabs, with special rates for gold and certain luxuries.
What is the difference between CGST and SGST?
CGST goes to the central government and SGST to the state — both apply on intrastate transactions and together equal the total GST.
When does IGST apply?
On interstate transactions and imports. IGST equals the total GST rate and is paid to the centre.
Does the calculator handle inclusive tax?
Yes — pick "Remove GST" and enter the total to see the base price and tax component.
Is my invoice data uploaded?
No — everything runs in your browser.