GST & penalty calculator for India (2026)
Add or remove GST at 0%, 0.25%, 3%, 5%, 18%, or 40% on any amount in rupees. Pick a category and the rate fills in automatically. The same tool also estimates late-fee and interest exposure for GSTR-3B, GSTR-1, TDS, and ITR filings. Rates aligned with the GST 2.0 structure effective 22 September 2025.
GST and penalty calculator
GST & penalty calculators
Price an invoice with the right GST split, or estimate the late fee and interest exposure on a missed filing before it hits your books.
Default 18% slab for any goods or services not listed above. Always cross-check the actual HSN/SAC code.
Tax summary
Invoice total
₹11,800
Rules last reviewed April 2026 against CBIC rate notifications and the 56th GST Council meeting.
How to use the GST calculator
Three inputs (mode, amount, and rate) give you the full invoice breakup. The tool is accurate for both GST-exclusive pricing (most B2B) and GST-inclusive pricing (most MRP-driven retail).
Pick add or remove
"Add GST" computes tax on a base amount for an outgoing invoice. "Remove GST" extracts the tax hidden inside an already GST-inclusive amount.
Pick category or rate
Choose a category and the calculator picks the GST 2.0 rate for you (0%, 0.25%, 3%, 5%, 18%, or 40%). You can also override the rate directly. Always verify against the HSN / SAC code on the specific goods or service.
Choose intra-state or inter-state
Same-state supply splits into equal CGST + SGST. Different-state (or export) supply shows IGST at the full rate. The calculator shows both totals and the tax-only component.
GST rate slabs in India (2026)
Under GST 2.0 (effective 22 September 2025) most goods and services fall into one of four primary slabs (0%, 5%, 18%, 40%), with two special rates retained (0.25% for rough precious stones, 3% for gold and jewellery). The 12% and 28% slabs were abolished. Additional compensation cess still applies on selected luxury items like large cars and tobacco. Always cross-check the rate against the current HSN (goods) or SAC (services) notification.
| Rate | Category | Common examples |
|---|---|---|
| 0% | Exempt / Nil-rated | Fresh milk, fruits, vegetables, unbranded atta, salt, educational services, healthcare by registered practitioners. |
| 0.25% | Rough precious and semi-precious stones | Rough diamonds (unprocessed), uncut precious and semi-precious stones under Chapter 71 of the Customs Tariff. |
| 3% | Gold, silver, jewellery | Gold (HSN 7108), silver (HSN 7106), gold and silver ornaments, jewellery, pearls, finished diamonds. |
| 5% | Essential goods and services | Packaged foods, tea, sugar, edible oils, life-saving drugs, railway and economy air travel, small restaurants, apparel and footwear up to Rs 1,000. |
| 18% | Standard rate (most goods and services) | Software and IT services, consulting, legal, accounting, marketing, restaurants with AC, mobile phones, laptops, appliances. |
| 40% | Luxury and sin goods | Large cars, tobacco and pan masala, aerated drinks, online gaming, betting, casino, luxury hotel stays above Rs 7,500. |
CGST, SGST, and IGST: how the split works
India charges GST through three simultaneous components. Which one applies depends on the place of supply, not on the physical address of the buyer or seller.
CGST
Central GST
Half of the rate, charged on every intra-state supply. Collected by the Centre. On an 18% intra-state invoice, CGST = 9%.
SGST / UTGST
State / UT GST
The other half of the rate, charged on every intra-state supply and kept by the destination state or UT. 9% on an 18% invoice.
IGST
Integrated GST
Full rate charged on inter-state supplies, exports, imports, and SEZ supplies. Collected by the Centre and later settled with the destination state.
Quick rule: supplier state and place of supply in the same state → CGST + SGST. Different states, or exports/imports → IGST. The calculator applies this automatically once you choose intra-state or inter-state.
Reverse GST calculation: extracting tax from a total
When you already have a GST-inclusive amount (MRP on a retail bill, a consolidated payment, an e-commerce payout), use the reverse formula to separate the tax from the base.
The formula
Base = Total × 100 / (100 + Rate)
GST = Total − Base
Worked example: 18% GST on ₹11,800
- Base = 11,800 × 100 / 118 = ₹10,000
- GST = 11,800 − 10,000 = ₹1,800
- CGST + SGST (intra-state) = ₹900 + ₹900
- IGST (inter-state) = ₹1,800
GST calculator FAQs
Short answers to the questions we get most often from SME owners, freelancers, and e-commerce sellers using the calculator.
How is GST calculated in India?+
GST is calculated as a percentage of the taxable value. For an outgoing invoice: GST amount = base value × rate / 100, invoice total = base + GST. For a reverse calculation (amount already includes GST): base = total × 100 / (100 + rate), GST = total − base. Intra-state supplies split GST equally between CGST and SGST; inter-state supplies are charged as IGST at the full rate.
What are the GST rate slabs in India in 2026?+
Under the GST 2.0 structure effective 22 September 2025 (per CBIC notifications following the 56th GST Council meeting), India now uses four primary slabs: 0% (exempt goods and essentials), 5% (everyday items and essential services), 18% (most goods and services including IT, consulting, appliances), and 40% (luxury and sin goods like large cars, tobacco, aerated drinks, online gaming). Two special rates are retained: 0.25% for rough precious stones and 3% for gold, silver, and jewellery. The old 12% and 28% slabs have been abolished; most 12% items moved to 5% and most 28% items moved to 18% or 40%. Always confirm the exact rate using the current HSN or SAC notification for your product or service.
How do I remove GST from a total amount?+
Use the formula: base value = total × 100 / (100 + rate). For example, on a ₹11,800 total at 18% GST, base = 11,800 × 100 / 118 = ₹10,000 and GST = ₹1,800. The Tax Garden GST calculator does this automatically when you switch to the "Remove GST" mode.
What is the difference between CGST, SGST, and IGST?+
CGST (Central GST) and SGST (State GST) are charged together on intra-state supplies. Each takes half the total rate. For example, 18% GST on a Hyderabad-to-Hyderabad invoice splits into 9% CGST + 9% SGST. IGST (Integrated GST) is charged at the full rate on inter-state supplies, exports, and imports, and the revenue is later shared between Centre and the destination state.
Is the GST calculator accurate for invoicing?+
Yes, the mathematics is exact. However, the actual tax on your invoice depends on the correct HSN/SAC classification, place of supply rules, reverse-charge applicability, and any exemptions or notifications that apply to your sector. For edge cases like mixed supplies, composite supplies, or supplies to SEZ units, confirm with a chartered accountant before filing.
Does GST apply to freelancers and small businesses?+
GST registration is mandatory if your aggregate turnover exceeds ₹40 lakh for goods (₹20 lakh for services, and ₹20/10 lakh in special-category states). Registered freelancers and SMEs charge GST on every taxable invoice and file GSTR-1 and GSTR-3B (monthly or quarterly under QRMP). Below the threshold, GST charging is optional unless the business makes inter-state supplies or sells through e-commerce operators.
Are reverse-charge transactions covered by this calculator?+
The calculator shows the GST math, but not the liability direction. Under reverse charge, the recipient pays GST directly to the government instead of the supplier. This is common for imports, GTA freight, and notified services from unregistered suppliers. The rate and amount are computed the same way; only the payer changes.
Is this GST calculator free to use?+
Yes, completely free with no signup. Tax Garden publishes it as a public utility for Indian businesses and accountants. If you want help turning these numbers into filed returns (GSTR-1, GSTR-3B, GSTR-9, reconciliation, and notice responses), our team handles it end-to-end from ₹2,100 per month.
Numbers are only half the work
GSTR-1, GSTR-3B, GSTR-9, reconciliation with GSTR-2B, and notice responses still need to happen on time. Tax Garden handles all of it from ₹2,100/month, with same-day filing acknowledgments and a dedicated CA on WhatsApp.