Validation APIs: Clean Your Data Before It Causes Problems

Bad data costs businesses an average of 25% of revenue. Validation APIs catch invalid emails before they bounce, verify phone numbers before SMS delivery, and check domain availability before purchase. They are the first line of defense for any application that accepts user input.

Why use a validation API?

Catch invalid data at the point of entry — not after it corrupts your database
Reduce bounce rates by verifying email addresses with MX record and disposable domain checks
Prevent fraud with breach detection, VPN/proxy identification, and username verification
Validate international formats (phone numbers, VAT IDs, addresses) without maintaining country-specific regex
Improve deliverability and user experience with real-time input validation

Validation APIs

12 APIs available in this category. All included in every plan.

Email Verify APIFeatured

Validate email addresses with syntax, MX, and disposable checks

Breach Check APIFeatured

Check if passwords or emails appear in known data breaches

CheckCheck APIFeatured

Domain availability checking with bulk support and TLD suggestions

WHOIS APIFeatured

Domain WHOIS lookup with parsed and raw data

Disposable Email API

Detect disposable and temporary email addresses

Phone Validate API

Validate, parse, and format international phone numbers

VAT Validate API

Validate EU VAT numbers via format check and VIES lookup

Address Verify API

Verify and standardize postal addresses for 100+ countries

Brand Intel API

Brand name analysis: scoring, trademark risk, and generation

NameCheck API

Check username availability across 50+ platforms

Bulk NameCheck API

Check multiple usernames across platforms at once

ForgeScore API

Brand name quality scoring on multiple criteria

How to validate data with Van Moose

Identify your validation needs

Common patterns: email verification on signup forms, phone validation before SMS, domain checks for registrars, VAT validation for B2B invoicing.

Integrate at the right point

Call the validation API server-side before saving data. For real-time UX, call on form blur events. Batch validation is available for bulk data cleaning.

Handle the response

Each validation API returns a structured result with a validity flag, risk score, and detailed breakdown. Use the granular fields to decide accept/reject/review.

Set up ongoing monitoring

Email addresses decay over time. Run periodic re-validation on your database to catch addresses that have become invalid since signup.

Quick example

Email Verify API

curl -X GET \
  "https://emailverify.vanmoose.cc" \
  -H "Authorization: Bearer vm_live_YOUR_API_KEY"

Replace vm_live_YOUR_API_KEY with your actual API key from the dashboard.

Frequently asked questions

How accurate is email validation?+

The Email Verify API checks syntax, MX records, and disposable email providers. It catches approximately 95% of invalid addresses without sending a test email. Combined with the Disposable Email API, you can block throwaway signups effectively.

Can I validate international phone numbers?+

Yes. The Phone Validate API supports international formats using the E.164 standard. It parses, formats, and validates numbers for 200+ countries, returning the carrier, line type, and country information.

What is the Breach Check API?+

The Breach Check API checks if an email address or password hash appears in known data breaches. Use it during signup to warn users about compromised credentials, or during login to prompt password changes.

Can I check domain availability in bulk?+

Yes. The CheckCheck API supports both single and bulk domain availability checks. It queries DNS and WHOIS data to determine if a domain is registered, and suggests alternative TLDs if the primary one is taken.

Start building with Validation APIs

Get 500 free requests/month. No credit card required. All 12 APIs in this category included.

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