GSTIN Verification API: complete guide
Validate Indian GSTIN numbers and retrieve registered business details.
What is GSTIN Verification API?
The GSTIN Verification API lets you validate a Goods and Services Tax Identification Number and return structured registration details for onboarding, KYC and compliance workflows.
How GSTIN Verification API works
GSTIN Verification API currently documents 2 endpoints: GET /v1/gstin/{gstin}, GET /v1/gstin/{gstin}/filings.
Who it is for
Typical jobs recorded on the listing include: Vendor onboarding; Invoice validation; KYC / compliance checks; Marketplace seller verification.
Key capabilities
GSTIN format and checksum validation
Structured business registration fields
Stable /v1 path
JSON responses
API key authentication
Limitations
Depends on upstream registry availability
Does not replace legal due diligence
Historical filings are not included in the basic response
Authentication
API key (header: X-SEEKER-Key)
Rate limits
From 10 req/min
Pricing
The listing shows a starting price of ₹0 and a free tier. Treat this as the catalog figure, not a negotiated contract.
How to use it
Example: GET /v1/gstin/{gstin}
Validate a GSTIN and return registration details.
Response fields from the listing:
GET /v1/gstin/{gstin}
X-SEEKER-Key: YOUR_API_KEYCommon errors
Verify GSTIN: 400 Invalid GSTIN format
Verify GSTIN: 401 Missing or invalid API key
Verify GSTIN: 404 GSTIN not found
Verify GSTIN: 429 Rate limit exceeded
Filing status: 400 Invalid GSTIN format
Filing status: 401 Missing or invalid API key
Filing status: 404 GSTIN not found
Related listings
Other india listings in this category: Pincode API. Compare only the fields each listing actually publishes.
Languages and frameworks
The listing names these SDK languages: cURL, JavaScript, Node.js, Python, PHP, Go, Java. Only those languages are treated as supported here.
How to choose
Review GSTIN Verification API on APISeeker and test it in the playground before integrating.
Key takeaways
- Validate Indian GSTIN numbers and retrieve registered business details.
- Listed under India on APISeeker.
- Uses API key (header: X-SEEKER-Key) authentication.
Frequently asked questions
Keep learning
- GuideAPI marketplace vs direct providerWhen a marketplace gateway helps, and when a direct contract is better.
- GuideAPI security basicsProtect keys, validate inputs and assume every network path can be hostile.
- GuideAPI observability basicsWhat to measure so incidents are diagnosable before customers complain.
- GuideAPI error handlingMap HTTP status codes to client behavior without leaking secrets.
Ready to integrate?
Compare plans, open docs, and try endpoints in the playground, then create a key when you are ready for production traffic.