GST Input Tax Credit (ITC) Calculator
Work out how much input tax credit you can actually claim — after blocked credits and the exempt-supply reversal — with a full line-by-line breakdown.
- Free — no sign-up
- Instant, on-screen results
- Built by our CA · CS team
- Rules cited on the page
Enter your figures — the result on the right updates as you type.
ITC computation breakdown
Get your GST returns filed & ITC reconciled by a CA
We match your ITC with GSTR-2B, apply 17(5) & Rule 42/43 correctly, and file GSTR-3B on time.
Disclaimer: Indicative estimate only. Actual eligible ITC depends on GSTR-2B matching, time-limit conditions, payment to suppliers within 180 days and exact Rule 42/43 workings. Rates & rules per the CGST Act.
What is Input Tax Credit?
Input Tax Credit (ITC) is the GST you pay to your suppliers on business purchases, which you can set off against the GST you collect on your sales. It stops tax cascading — you only pay GST on the value you add. But not every rupee of input GST is claimable: some credits are permanently blocked under Section 17(5), and a portion must be reversed under Rule 42/43 when inputs are used for exempt supplies or personal purposes.
Blocked & reversed credits — the two deductions
Your eligible ITC is the total input GST minus two things: credits that are blocked outright under Section 17(5), and the portion that has to be reversed under Rule 42/43 because inputs were used for exempt or non-business purposes.
| Motor vehicles (≤13 seats) & related | Blocked |
| Food, beverages & outdoor catering | Blocked |
| Club, health & fitness memberships | Blocked |
| Works contract for immovable property | Blocked |
| Goods/services for personal use | Blocked |
| Free samples & goods lost/stolen/gifted | Blocked |
| Rule 42 — inputs & input services | Common credit |
| Rule 43 — capital goods | Over 60 months |
| Trigger — exempt supplies | Reverse pro-rata |
| Trigger — personal / non-business use | Reverse pro-rata |
| Ratio | Exempt ÷ total T/O |
How eligible ITC is calculated
Start from total input GST → remove blocked 17(5) credits → remove the Rule 42/43 reversal for exempt/personal use → what's left is your net eligible ITC (never below zero). Here are three worked examples:
Key terms explained
Section 17(5) — blocked credits
A list of purchases on which ITC is never allowed, regardless of business use — motor vehicles for passenger transport, food & catering, club memberships, works contracts for immovable property and goods for personal consumption.
Rule 42 & 43 — reversal
When common inputs feed both taxable and exempt (or personal) supplies, the exempt share of credit must be reversed pro-rata. Rule 42 covers inputs & input services; Rule 43 spreads capital-goods credit over 60 months.
GSTR-2B matching
ITC can be claimed only if the invoice is reflected in your auto-drafted GSTR-2B. If your supplier hasn't reported it, the credit isn't available that period — reconciliation before filing GSTR-3B is essential.
180-day payment rule
If you don't pay the supplier (value + tax) within 180 days of the invoice, any ITC already claimed must be reversed with interest, and can be reclaimed once payment is made.
Questions people ask
Short answers on GST ITC Calculator. Tap a question to open it.
01What are the conditions for claiming input tax credit?
Section 16 requires a valid tax invoice, actual receipt of the goods or services, the tax to have been paid by the supplier, the invoice to appear in your GSTR-2B, and the return to be filed. The supplier's payment must also be made within 180 days of the invoice date.
02Which credits are blocked?
Section 17(5) blocks credit on motor vehicles for personal use, food and beverages, outdoor catering, club and health-fitness memberships, health insurance except where mandated, works contract and construction of immovable property on own account, and goods lost, stolen, destroyed or given as free samples.
03What is the 180-day payment rule?
If you do not pay the supplier within 180 days of the invoice date, the credit already availed must be reversed with interest. It can be reclaimed once payment is made, with no time limit on the re-availment.
04What is the deadline for claiming ITC on an invoice?
30 November following the end of the financial year, or the date of filing the annual return for that year, whichever is earlier. After that the credit lapses.
05What if an invoice does not appear in my GSTR-2B?
The credit cannot be taken. Follow up with the supplier to report it in their GSTR-1 — the credit becomes available in the 2B of the period in which they report it.
More GST tools
Picked from the same shelf. Every tool is free and runs in your browser.
Disclaimer: This tool gives indicative results for general guidance only and is not professional advice. Please verify with a qualified CA before acting on the numbers.