Validate email addresses in real time

The problem

A single regex either rejects valid addresses or waves through typos and disposable junk. Bad emails inflate bounce rates, poison deliverability, and quietly break every downstream sync that assumes the field is clean.

What you get

• Syntactic validation that follows the real rules, not a naive pattern
• Normalizes the address so your stored value is consistent
• Flags obviously invalid input at the point of entry
• Fast enough to run inline on form submit

Call it in one request

Plain HTTPS and JSON against /api/v1/validate-email. Use the SDK for typed calls, or hit the endpoint directly — same contract either way.

curl https://zapinner.com/api/v1/validate-email \
  -H "Authorization: Bearer zap_live_••••••" \
  -H "Content-Type: application/json" \
  -d '{"data":[{"email":"John@Example.com"},{"email":"bad@"}],"options":{"field":"email"}}'

const res = await fetch("https://zapinner.com/api/v1/validate-email", {
  method: "POST",
  headers: {
    Authorization: "Bearer zap_live_••••••",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
  "data": [
    {
      "email": "John@Example.com"
    },
    {
      "email": "bad@"
    }
  ],
  "options": {
    "field": "email"
  }
}),
})
const data = await res.json()

import { Zapinner } from "@zapinner/sdk"

const zap = new Zapinner({ apiKey: process.env.ZAPINNER_API_KEY })

const result = await zap.validateEmail({
  "data": [
    {
      "email": "John@Example.com"
    },
    {
      "email": "bad@"
    }
  ],
  "options": {
    "field": "email"
  }
})

Frequently asked

Does it check whether the mailbox actually exists?

It validates and normalizes the address structure and catches clearly invalid input. Treat it as the fast first line of defense at ingestion rather than a live mailbox ping.

Can I run it on a signup form?

Yes. The endpoint is designed to run inline on submit so you reject malformed addresses before they enter your database.

What comes back in the response?

A validity signal plus the normalized address, so you can store a consistent value and act on invalid input in the same call.

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