Validate users.
Block bad actors.
Ship with confidence.

Production-ready email, phone, and IP validation API. Start free with 1,000 credits/month — no credit card required.

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Quick Start

One endpoint, any language

Add validation in minutes. No SDK — plain HTTP, clean JSON responses.

# Email validation
curl -X POST https://api.checkharbor.com/v1/email/validate \
  -H 'x-api-key: ch_live_••••••••' \
  -H 'content-type: application/json' \
  -d '{"email":"user@gmail.com"}'

# IP intelligence
curl -X POST https://api.checkharbor.com/v1/ip/intel \
  -H 'x-api-key: ch_live_••••••••' \
  -H 'content-type: application/json' \
  -d '{"ip":"1.2.3.4"}'

const res = await fetch('https://api.checkharbor.com/v1/email/validate', {
  method: 'POST',
  headers: {
    'x-api-key': process.env.CHECKHARBOR_API_KEY,
    'content-type': 'application/json',
  },
  body: JSON.stringify({ email: 'user@gmail.com' }),
})

const { valid_syntax, deliverability, score } = await res.json()
console.log(`Score: ${score}, Status: ${deliverability}`)

import httpx

resp = httpx.post(
    "https://api.checkharbor.com/v1/email/validate",
    headers={"x-api-key": "ch_live_••••••••"},
    json={"email": "user@gmail.com"},
)
data = resp.json()
print(data["deliverability"], data["score"])

Why Check Harbor

Everything you need, nothing you don't

Built for developers and growth teams who need reliable validation without complexity or surprise costs.

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