GST Calculator
Calculate GST from a selected rate and price basis. Compare inclusive and exclusive amounts without assuming a product classification.
Browser-based · No signup · Transparent assumptions
- 01Enter your values
- 02Adjust your settings
- 03Review your results
Enter an amount to begin
Your base, GST, CGST/SGST or IGST split, and total will appear here.
| Rate | GST amount | Total |
|---|
Rate presets do not establish HSN/SAC eligibility. 12% and 28% are retained as legacy scenarios; verify the supply date and notification.
Calculations run in this browser. Shared URLs can contain input values. Review links before sharing financial, dietary or birth-date information.
When to use this calculator
Check the tax component of an inclusive price or add a chosen GST rate to an exclusive amount. Select the applicable rate yourself and compare the displayed CGST/SGST or IGST split with the transaction context.
Review the worked example and assumptions below, then use the supported report or copy controls to keep the result with its inputs. Calculations run in this browser; a shared URL can include the values you entered.
How to use GST Calculator
- Enter the amount and choose whether GST is included or added on top.
- Select the applicable rate and intra-state or inter-state supply.
- Review the base amount, tax split and invoice total, then copy or export.
Adding and removing GST
Exclusive tax is base multiplied by rate/100. For an inclusive amount, base is total divided by (1 + rate/100). Intra-state CGST and SGST split the selected rate equally; inter-state supply uses IGST. Presets are calculation shortcuts, not a classification engine.
Worked example
INR 1,000 exclusive at 18%: tax INR 180; total INR 1,180
INR 1,180 inclusive at 18%: base INR 1,000; tax INR 180
Intra-state split: CGST INR 90 + SGST INR 90Assumptions and limits
September 2025 reforms introduced broad 5% and 18% bands and a special 40% rate, with exceptions and later notifications. Legacy rates remain available for historical/custom scenarios. Verify HSN/SAC, effective date and applicable notification. This excludes compensation cess, reverse charge, ITC and statutory invoice rounding. Currency changes notation only.
Reference: Government of India: 56th GST Council rate decisions. Model/source review: 19 October 2026. See the tool-specific scope and precision limits above.
Frequently asked questions
Which GST rate should I use?
Check the applicable HSN/SAC classification and effective notification. This calculator does not determine liability or exemptions.
Why is removing 18% different from subtracting 18%?
An inclusive amount already contains tax. Divide by 1.18 to recover the base; subtracting 18% of the total overstates the tax.
Can I use a custom rate?
Yes. Enter any rate from 0% to 100%, including historical or special rates.
A practical input scenario
Choose the arithmetic mode corresponding to the amount you have, enter a rate for your scenario and inspect the displayed base and tax portions.
Read the scope alongside the result
This tool does not determine applicable rates, exemptions or classification. Existing exclusions remain; this SEO update does not verify tax rules or notifications.