Tax ID ValidatorTax ID Validator API

OnlineCredit Usage:1 per callRefreshed 1 month ago
avg: 153ms|p50: 147ms|p75: 157ms|p90: 168ms|p99: 190ms

Tax ID Validator is a comprehensive tool for validating US Tax IDs including Social Security Numbers (SSN), Employer Identification Numbers (EIN), and Individual Taxpayer Identification Numbers (ITIN).

The Tax ID Validator API provides reliable and fast access to tax id validator data through a simple REST interface. Built for developers who need consistent, high-quality results with minimal setup time.

To use Tax ID Validator, you need an API key. You can get one by creating a free account and visiting your dashboard.

GET Endpoint

URL
https://api.apiverve.com/v1/taxidvalidator

Code Examples

Here are examples of how to call the Tax ID Validator API in different programming languages:

cURL Request
curl -X GET \
  "https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789" \
  -H "X-API-Key: your_api_key_here"
JavaScript (Fetch API)
const response = await fetch('https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789', {
  method: 'GET',
  headers: {
    'X-API-Key': 'your_api_key_here',
    'Content-Type': 'application/json'
  }
});

const data = await response.json();
console.log(data);
Python (Requests)
import requests

headers = {
    'X-API-Key': 'your_api_key_here',
    'Content-Type': 'application/json'
}

response = requests.get('https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789', headers=headers)

data = response.json()
print(data)
Node.js (Native HTTPS)
const https = require('https');
const url = require('url');

const options = {
  method: 'GET',
  headers: {
    'X-API-Key': 'your_api_key_here',
    'Content-Type': 'application/json'
  }
};

const req = https.request('https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789', options, (res) => {
  let data = '';
  res.on('data', (chunk) => data += chunk);
  res.on('end', () => console.log(JSON.parse(data)));
});

req.end();
PHP (cURL)
<?php

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL, 'https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'GET');
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'X-API-Key: your_api_key_here',
    'Content-Type: application/json'
]);

$response = curl_exec($ch);
curl_close($ch);

$data = json_decode($response, true);
print_r($data);

?>
Go (net/http)
package main

import (
    "fmt"
    "io"
    "net/http"

)

func main() {
    req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789", nil)

    req.Header.Set("X-API-Key", "your_api_key_here")
    req.Header.Set("Content-Type", "application/json")

    client := &http.Client{}
    resp, err := client.Do(req)
    if err != nil {
        panic(err)
    }
    defer resp.Body.Close()

    body, _ := io.ReadAll(resp.Body)
    fmt.Println(string(body))
}
Ruby (Net::HTTP)
require 'net/http'
require 'json'

uri = URI('https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true

request = Net::HTTP::Get.new(uri)
request['X-API-Key'] = 'your_api_key_here'
request['Content-Type'] = 'application/json'

response = http.request(request)
puts JSON.pretty_generate(JSON.parse(response.body))
C# (HttpClient)
using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

class Program
{
    static async Task Main(string[] args)
    {
        using var client = new HttpClient();
        client.DefaultRequestHeaders.Add("X-API-Key", "your_api_key_here");

        var response = await client.GetAsync("https://api.apiverve.com/v1/taxidvalidator?taxid=123-45-6789");
        response.EnsureSuccessStatusCode();

        var responseBody = await response.Content.ReadAsStringAsync();
        Console.WriteLine(responseBody);
    }
}

Authentication

The Tax ID Validator API requires authentication via API key. Include your API key in the request header:

Required Header
X-API-Key: your_api_key_here

Learn more about authentication →

Interactive API Playground

Test the Tax ID Validator API directly in your browser with live requests and responses.

Parameters

The following parameters are available for the Tax ID Validator API:

Validate Tax ID

ParameterTypeRequiredDescriptionDefaultExample
taxidstringrequired
The US Tax ID to validate (SSN, EIN, or ITIN format)
-123-45-6789

Response

The Tax ID Validator API returns responses in JSON, XML, YAML, and CSV formats:

Example Responses

JSON Response
200 OK
{
  "status": "ok",
  "error": null,
  "data": {
    "valid": true,
    "taxid": "123-45-6789",
    "type": "SSN",
    "type_full": "Social Security Number",
    "format": "XXX-XX-XXXX",
    "normalized": "123-45-6789",
    "digits_only": "123456789",
    "masked": "***-**-6789",
    "last4": "6789",
    "validation_details": {
      "format_valid": true,
      "area_number_valid": true,
      "group_number_valid": true,
      "serial_number_valid": true
    },
    "error": null
  }
}
XML Response
200 OK
<?xml version="1.0" encoding="UTF-8"?>
<response>
  <status>ok</status>
  <error xsi:nil="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/>
  <data>
    <valid>true</valid>
    <taxid>123-45-6789</taxid>
    <type>SSN</type>
    <type_full>Social Security Number</type_full>
    <format>XXX-XX-XXXX</format>
    <normalized>123-45-6789</normalized>
    <digits_only>123456789</digits_only>
    <masked>***-**-6789</masked>
    <last4>6789</last4>
    <validation_details>
      <format_valid>true</format_valid>
      <area_number_valid>true</area_number_valid>
      <group_number_valid>true</group_number_valid>
      <serial_number_valid>true</serial_number_valid>
    </validation_details>
    <error xsi:nil="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/>
  </data>
</response>
YAML Response
200 OK
status: ok
error: null
data:
  valid: true
  taxid: 123-45-6789
  type: SSN
  type_full: Social Security Number
  format: XXX-XX-XXXX
  normalized: 123-45-6789
  digits_only: '123456789'
  masked: '***-**-6789'
  last4: '6789'
  validation_details:
    format_valid: true
    area_number_valid: true
    group_number_valid: true
    serial_number_valid: true
  error: null
CSV Response
200 OK
keyvalue
validtrue
taxid123-45-6789
typeSSN
type_fullSocial Security Number
formatXXX-XX-XXXX
normalized123-45-6789
digits_only123456789
masked***-**-6789
last46789
validation_details{format_valid:true,area_number_valid:true,group_number_valid:true,serial_number_valid:true}
error

Response Structure

All API responses follow a consistent structure with the following fields:

FieldTypeDescriptionExample
statusstringIndicates whether the request was successful ("ok") or failed ("error")ok
errorstring | nullContains error message if status is "error", otherwise nullnull
dataobject | nullContains the API response data if successful, otherwise null{...}

Learn more about response formats →

Response Data Fields

When the request is successful, the data object contains the following fields:

Response fields marked with Premium are available exclusively on paid plans.View pricing
FieldTypeSample ValueDescription
validbooleantrueWhether the Tax ID passed validation checks
taxidstring"123-45-6789"The formatted Tax ID with standard formatting applied
typePremiumstring"SSN"Abbreviated Tax ID type: SSN, EIN, or ITIN
type_fullPremiumstring"Social Security Number"Full name of Tax ID type like Social Security Number
formatPremiumstring"XXX-XX-XXXX"Expected format pattern for the Tax ID type
normalizedstring"123-45-6789"Tax ID normalized to standard format with hyphens
digits_onlystring"123456789"Tax ID with all non-numeric characters removed
maskedstring"***-**-6789"Tax ID with sensitive digits masked for privacy protection
last4string"6789"Last four digits of the Tax ID only
validation_detailsobject{...}-
â”” format_validPremiumbooleantrueWhether the Tax ID matches the expected format
â”” area_number_validPremiumbooleantrueWhether SSN area number is valid (first three digits)
â”” group_number_validPremiumbooleantrueWhether SSN group number is valid (middle two digits)
â”” serial_number_validPremiumbooleantrueWhether SSN serial number is valid (last four digits)
errorobjectnullError message if validation failed, otherwise null

Headers

Required and optional headers for Tax ID Validator API requests:

Header NameRequiredExample ValueDescription
X-API-Keyrequiredyour_api_key_hereYour APIVerve API key. Found in your dashboard under API Keys.
Acceptoptionalapplication/jsonSpecify response format: application/json (default), application/xml, or application/yaml
User-AgentoptionalMyApp/1.0Identifies your application for analytics and debugging purposes
X-Request-IDoptionalreq_123456789Custom request identifier for tracking and debugging requests
Cache-Controloptionalno-cacheControl caching behavior for the request and response

Learn more about request headers →

GraphQL AccessALPHA

Access Tax ID Validator through GraphQL to combine it with other API calls in a single request. Query only the tax id validator data you need with precise field selection, and orchestrate complex data fetching workflows.

Test Tax ID Validator in the GraphQL Explorer to confirm availability and experiment with queries.

Credit Cost: Each API called in your GraphQL query consumes its standard credit cost.

GraphQL Endpoint
POST https://api.apiverve.com/v1/graphql
GraphQL Query Example
query {
  taxidvalidator(
    input: {
      taxid: "123-45-6789"
    }
  ) {
    valid
    taxid
    type
    type_full
    format
    normalized
    digits_only
    masked
    last4
    validation_details {
      format_valid
      area_number_valid
      group_number_valid
      serial_number_valid
    }
    error
  }
}

Note: Authentication is handled via the x-api-key header in your GraphQL request, not as a query parameter.

CORS Support

The Tax ID Validator API supports Cross-Origin Resource Sharing (CORS) with wildcard configuration, allowing you to call Tax ID Validator directly from browser-based applications without proxy servers.

CORS HeaderValueDescription
Access-Control-Allow-Origin*Accepts requests from any origin
Access-Control-Allow-Methods*Accepts any HTTP method
Access-Control-Allow-Headers*Accepts any request headers

Browser Usage: You can call Tax ID Validator directly from JavaScript running in the browser without encountering CORS errors. No proxy server or additional configuration needed.

Learn more about CORS support →

Rate Limiting

Tax ID Validator API requests are subject to rate limiting based on your subscription plan. These limits ensure fair usage and maintain service quality for all Tax ID Validator users.

PlanRate LimitDescription
Free5 requests/minHard rate limit enforced - exceeding will return 429 errors
StarterNo LimitProduction ready - standard traffic priority
ProNo LimitProduction ready - preferred traffic priority
MegaNo LimitProduction ready - highest traffic priority

Learn more about rate limiting →

Rate Limit Headers

When rate limits apply, each Tax ID Validator response includes headers to help you track your usage:

HeaderDescription
X-RateLimit-LimitMaximum number of requests allowed per time window
X-RateLimit-RemainingNumber of requests remaining in the current window
X-RateLimit-ResetUnix timestamp when the rate limit window resets

Handling Rate Limits

Free Plan: When you exceed your rate limit, Tax ID Validator returns a 429 Too Many Requests status code. Your application should implement appropriate backoff logic to handle this gracefully.

Paid Plans: No rate limiting or throttling applied. All paid plans (Starter, Pro, Mega) are production-ready.

Best Practices for Tax ID Validator:

  • Monitor the rate limit headers to track your Tax ID Validator usage (Free plan only)
  • Cache tax id validator responses where appropriate to reduce API calls
  • Upgrade to Pro or Mega for guaranteed no-throttle Tax ID Validator performance

Note: Tax ID Validator rate limits are separate from credit consumption. You may have credits remaining but still hit rate limits when using Tax ID Validator on Free tier.

Error Codes

The Tax ID Validator API uses standard HTTP status codes to indicate success or failure:

CodeMessageDescriptionSolution
200OKRequest successful, data returnedNo action needed - request was successful
400Bad RequestInvalid request parameters or malformed requestCheck required parameters and ensure values match expected formats
401UnauthorizedMissing or invalid API keyInclude x-api-key header with valid API key from dashboard
403ForbiddenAPI key lacks permission or insufficient creditsCheck credit balance in dashboard or upgrade plan
429Too Many RequestsRate limit exceeded (Free: 5 req/min)Implement request throttling or upgrade to paid plan
500Internal Server ErrorServer error occurredRetry request after a few seconds, contact support if persists
503Service UnavailableAPI temporarily unavailableWait and retry, check status page for maintenance updates

Learn more about error handling →

Need help? Contact support with your X-Request-ID for assistance.

Integrate Tax ID Validator with SDKs

Get started quickly with official Tax ID Validator SDKs for your preferred language. Each library handles authentication, request formatting, and error handling automatically.

Available for Node.js, Python, C#/.NET, and Android/Java. All SDKs are open source and regularly updated.

Integrate Tax ID Validator with No-Code API Tools

Connect the Tax ID Validator API to your favorite automation platform without writing code. Build workflows that leverage tax id validator data across thousands of apps.

All platforms use your same API key to access Tax ID Validator. Visit our integrations hub for step-by-step setup guides.

Frequently Asked Questions

How do I get an API key for Tax ID Validator?
Sign up for a free account at dashboard.apiverve.com. Your API key will be automatically generated and available in your dashboard. The same key works for Tax ID Validator and all other APIVerve APIs. The free plan includes 1,000 credits plus a 500 credit bonus.
How many credits does Tax ID Validator cost?

Each successful Tax ID Validator API call consumes credits based on plan tier. Check the pricing section above for the exact credit cost. Failed requests and errors don't consume credits, so you only pay for successful tax id validator lookups.

Can I use Tax ID Validator in production?

The free plan is for testing and development only. For production use of Tax ID Validator, upgrade to a paid plan (Starter, Pro, or Mega) which includes commercial use rights, no attribution requirements, and guaranteed uptime SLAs. All paid plans are production-ready.

Can I use Tax ID Validator from a browser?
Yes! The Tax ID Validator API supports CORS with wildcard configuration, so you can call it directly from browser-based JavaScript without needing a proxy server. See the CORS section above for details.
What happens if I exceed my Tax ID Validator credit limit?

When you reach your monthly credit limit, Tax ID Validator API requests will return an error until you upgrade your plan or wait for the next billing cycle. You'll receive notifications at 80% and 95% usage to give you time to upgrade if needed.

What's Next?

Continue your journey with these recommended resources

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