VyaparKit

GSTIN Checker

Verify a GSTIN's structure, check digit, PAN and state instantly. Free GST number checker.

Free · no login neededMade for India · ₹, GST, UPI, WhatsApp

In short

A GSTIN checker validates a 15-character GST Identification Number by checking its structure and check digit and decoding the state and PAN inside it. VyaparKit's free GSTIN validator works offline in the browser, tells you whether the format and checksum are correct, and shows the state, PAN, entity type and registration number, without contacting the GST portal.

Example: 27AAPFU0939F1ZV

Enter a 15-character GSTIN to validate it and decode the state and PAN.

What is the GSTIN format?

15 characters: 2-digit state code, 10-character PAN, 1 entity number, the letter Z, and a check digit computed from the first 14 characters.

Does this verify the business exists?

No. It validates the format and check digit, which catches typos. Live status (active/cancelled) and the legal name require the GST portal or a paid API.

What does the 4th character of PAN mean?

P = individual, C = company, F = firm/LLP, H = HUF, T = trust, A = association of persons, and so on.

Why does my GSTIN fail?

Most failures are a mistyped character. Check O vs 0 and I vs 1, and confirm the 14th character is Z.

About the gstin checker tool

A GSTIN is the 15-character number every GST-registered business in India receives, such as 27AAPFU0939F1ZV. It is built from the state code, the PAN, an entity number, the letter Z and a check digit. Businesses need to record customer and supplier GSTINs on invoices, e-way bills and returns, and a single wrong character means the buyer's input tax credit does not show up in GSTR-2B.

Typing a GSTIN from a visiting card or a WhatsApp photo is where errors creep in: O for 0, I for 1, a missed character. The GST portal search catches this but needs login and a captcha for each check. VyaparKit's GSTIN checker runs the same structural rules and the mod-36 checksum instantly as you type, flags a mistyped character, and decodes the state and PAN type so you can see at a glance whether '27' really means Maharashtra and 'F' really means a partnership firm.

This is a format and checksum check only; it does not confirm that the registration is active or fetch the legal name. For live status use the GST portal. Inside VyaparKit, the same validation runs when you save a customer or vendor, so invoices never carry a malformed GSTIN.

How to check a GSTIN number online

  1. 1

    Enter the 15-character GSTIN

    Type or paste the number into the GSTIN box. Letters are converted to upper case automatically and the box accepts exactly 15 characters.

  2. 2

    Watch for the verdict

    As soon as 15 characters are present the result shows 'Valid GSTIN format' with a green tick or 'Invalid GSTIN' with the reason, such as a checksum mismatch or a bad state code.

  3. 3

    Read the decoded details

    The panel lists State with its code, the 10-character PAN, the entity type derived from the PAN's 4th character, the registration number within the state and whether the check digit matches.

  4. 4

    Fix typos if flagged

    If the check digit does not match, compare O against 0 and I against 1, and confirm the 14th character is Z. Re-enter and the result updates immediately.

  5. 5

    Confirm live status separately

    For a new customer or vendor, verify the active status and legal name on the GST portal's 'Search Taxpayer' page before extending credit or claiming input tax.

How a GSTIN is built, with a worked example

  • Positions 1 to 2: state code from the census list. In 27AAPFU0939F1ZV, 27 is Maharashtra. Other common codes: 07 Delhi, 29 Karnataka, 33 Tamil Nadu, 24 Gujarat, 09 Uttar Pradesh.
  • Positions 3 to 12: the 10-character PAN of the business, AAPFU0939F in the example. PAN format is five letters, four digits, one letter.
  • The 4th character of the PAN (6th of the GSTIN) gives the entity type: P individual, C company, F firm or LLP, H HUF, T trust, A association of persons, G government. The example's F means a partnership firm.
  • Position 13: entity number for that PAN within the state, 1 to 9 then A to Z. '1' in the example means the first registration of that PAN in Maharashtra.
  • Position 14: the letter Z by default, reserved for future use.
  • Position 15: check digit. Each of the first 14 characters is converted to a value (0 to 9, A = 10 to Z = 35), multiplied by 1 or 2 alternately, the quotient and remainder on division by 36 are added, and the check digit is (36 − sum mod 36) mod 36 converted back. For the example it is V.
  • A valid checksum proves the number is well formed, not that it belongs to the business you are dealing with or that the registration is still active.
  • Under Rule 46 the buyer's GSTIN must appear on every B2B tax invoice; input tax credit flows only if it matches the GSTIN in the supplier's GSTR-1.

Who uses the gstin checker

Accounts teams onboarding vendors

Before adding a new supplier to the vendor master, the accounts executive checks the GSTIN on the quotation so bills are not rejected later.

Sales staff creating B2B invoices

A distributor's billing clerk in Indore validates the GSTIN a retailer dictates on the phone before printing the invoice.

CA firms during reconciliation

While matching GSTR-2B with purchase registers, staff check whether a mismatch is caused by a mistyped GSTIN rather than a missing filing.

E-commerce and marketplace sellers

Sellers collecting GSTINs from bulk buyers for B2B invoices catch invalid numbers at order time instead of after dispatch.

GSTIN Checker: frequently asked questions

How can I verify a GSTIN number?
Two levels. First, a format and checksum check like this tool confirms the 15 characters are structurally valid and the check digit matches, which catches typos. Second, the GST portal's 'Search Taxpayer' page confirms the registration is active, shows the legal and trade name and the registration date. Do both for a new trading partner.
What does each part of a GSTIN mean?
The first two digits are the state code (27 for Maharashtra), the next ten characters are the PAN, the thirteenth is the entity number for that PAN in the state, the fourteenth is Z, and the fifteenth is a check digit computed from the first fourteen. So 27AAPFU0939F1ZV is a Maharashtra registration of the firm holding PAN AAPFU0939F.
Can one PAN have more than one GSTIN?
Yes. A business needs a separate GSTIN in each state where it has a place of business, and it may take additional registrations within a state for separate business verticals. The 13th character counts these: 1 for the first registration, 2 for the second, then A to Z once digits run out.
Why does a GSTIN fail the check digit test?
Almost always a typing error. The check digit is calculated from the other 14 characters, so changing any one of them breaks the match. Look for O typed as 0, I as 1, S as 5, B as 8, and swapped adjacent characters. If the number was copied from a printed invoice, ask the supplier to send it as text.
Does the GSTIN checker show whether the registration is active or cancelled?
No. It runs entirely in your browser and only checks structure and checksum. A cancelled or suspended GSTIN can still pass this test. For active status, filing frequency and the legal name, use the GST portal or an API-based verification service before claiming input tax credit on a supplier's invoices.
Is a GSTIN the same as a GST number?
Yes. GSTIN, GST number and GST registration number all refer to the same 15-character identifier. It is different from the PAN (10 characters, issued by the Income Tax department) although the PAN is embedded inside the GSTIN, and different from the TAN used for TDS.

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