---
title: "ZeroBounce / Guess a person's email at a domain"
description: "ZeroBounce tool zerobounce-guessformat on looot: input fields, $0.01 per call, output shape, and code to run it with curl, JavaScript or Python."
sidebar:
  hidden: true
---

{/* Generated by scripts/generate-api-reference.mjs from data/api-reference.json. Do not edit. */}

Guesses the most likely email address for a person at a domain. Send domain, first_name and last_name (middle_name optional). Returns email, email_confidence and company_name. Billed 1 credit per Valid guess.

- **Tool id:** `zerobounce-guessformat`
- **Provider:** [ZeroBounce](/providers/zerobounce)
- **Job:** [Detect a company's email address format](/reference/jobs/people-email-pattern) (`people.email.pattern`)
- **Price:** $0.01 per call. A call that fails at the provider costs $0.

## Inputs

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `domain` | string | yes | Domain to search, e.g. company.com. |
| `first_name` | string | no |   |
| `last_name` | string | no |   |
| `middle_name` | string | no |   |

## Output

Shape of the run's `result`, checked against 1 real answer:

```txt
{ email, domain, company_name, did_you_mean, failure_reason, email_confidence }
```

## Run it

Every call needs your API token in `LOOOT_TOKEN`; [Sign in](/get-started/sign-in#use-the-token-in-scripts-and-agents) shows how to get one. Each run also needs a new idempotency key, so a retry never pays twice. With `wait: 30` the answer comes back inline when the run ends within 30 seconds. Otherwise you get the running run back: poll `GET /v1/runs/<runId>`.

Example input with placeholder values:

<CodeGroup>

```bash curl
curl -X POST "https://api.looot.ai/v1/runs" \
  -H "Authorization: Bearer $LOOOT_TOKEN" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{"endpointId":"zerobounce-guessformat","input":{"domain":"example.com"},"wait":30}'
```

```js JavaScript
const response = await fetch("https://api.looot.ai/v1/runs", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.LOOOT_TOKEN}`,
    "Content-Type": "application/json",
    "Idempotency-Key": crypto.randomUUID(),
  },
  body: JSON.stringify({
    endpointId: "zerobounce-guessformat",
    input: {
      domain: "example.com",
    },
    wait: 30,
  }),
});
const run = await response.json();
console.log(run.status, run.result);
```

```python Python
import os
import uuid

import requests

response = requests.post(
    "https://api.looot.ai/v1/runs",
    headers={
        "Authorization": f"Bearer {os.environ['LOOOT_TOKEN']}",
        "Idempotency-Key": str(uuid.uuid4()),
    },
    json={
        "endpointId": "zerobounce-guessformat",
        "input": {
            "domain": "example.com",
        },
        "wait": 30,
    },
    timeout=90,
)
run = response.json()
print(run["status"], run.get("result"))
```

</CodeGroup>

To let looot pick among every provider of this job instead, send `job:people.email.pattern` as `endpointId`; see [the job page](/reference/jobs/people-email-pattern).