GSTIN Validator

How GSTIN Validation Works

A GSTIN (Goods and Services Tax Identification Number) is a 15-digit alphanumeric code assigned to every registered taxpayer in India. The structure is: SS PPPPP 9999 P N Z C where SS is the state code (01–38), PPPPP9999P is the PAN, N is the entity number, Z is always 'Z', and C is a check digit computed using the Luhn mod-36 algorithm.

What This Tool Checks

• Format validation — verifies the 15-character alphanumeric pattern
• Luhn mod-36 checksum — validates the check digit (15th character) using the algorithm specified by GSTN
• State code — extracts and identifies the state/UT from the first 2 digits (all 37 Indian states and UTs supported)
• PAN extraction — shows the 10-character PAN embedded in positions 3–12
• Entity type — identifies the business type from the 14th character (proprietorship, LLP, company, HUF, etc.)

This tool works entirely in your browser — no data is sent to any server. It's free, instant, and works offline. For real-time GSTIN verification against the GST portal, sign up for 1010 which includes live portal verification during invoice creation.

GSTIN State Codes Reference