---
title: "Quick Start"
description: "Make your first SignupSieve API call in 2 minutes: get a free key, check an email address and read the verdict."
canonical_url: "https://signupsieve.pages.dev/docs"
---

> Index of every page on this site: [llms.txt](https://signupsieve.pages.dev/llms.txt)

# SignupSieve API docs

**Catch fake signups, not just bad emails.**

SignupSieve tells you whether a real, unique person is behind an email address. One call returns:

- a **human_score** from 0 to 100,
- a **verdict**: `allow`, `review` or `block`,
- the **reasons** behind it.

It never contacts mail servers, answers in milliseconds, and learns from the outcomes you report.

## Get an API key

1. Open SignupSieve on [RapidAPI](https://rapidapi.com/KeirStephanCTombocon/api/signupsieve) and sign in (free).
2. Subscribe to the **Basic** plan: 1,000 checks a month, no card needed.
3. Copy your key and host from the **Code Snippets** panel.

> **Keep your RapidAPI key on your server.** Never put it in browser or mobile app code.

## Quick start (first call in 2 minutes)

Send the address in a `POST` body. Add the user's IP if you have it; this is optional but catches more bots.

```bash
curl -X POST "https://signupsieve.p.rapidapi.com/v1/check" \
  -H "Content-Type: application/json" \
  -H "X-RapidAPI-Key: YOUR_RAPIDAPI_KEY" \
  -H "X-RapidAPI-Host: signupsieve.p.rapidapi.com" \
  -d '{"email": "maria.santos@gmail.com", "ip": "203.177.10.10"}'
```

```json
{
  "email": "maria.santos@gmail.com",
  "canonical": "mariasantos@gmail.com",
  "account_type": "free",
  "role_account": false,
  "disposable": false,
  "relay": false,
  "deliverable_domain": true,
  "mail_provider": "google",
  "human_score": 94,
  "verdict": "allow",
  "reasons": ["natural_name", "dotted_gmail"],
  "ip": { "tor": false, "signups_from_ip": 1 },
  "check_id": "chk_AXDmekmC35NL1mpGtCtC...",
  "model": "baseline"
}
```

> Use the exact host and key shown in the **Code Snippets** panel on our RapidAPI listing. The host above is an example.

## Privacy

- Email and IP addresses are analyzed, then forgotten. **Never stored, never sold.**
- We never send email or contact mail servers, so checks are silent and your IP is never blacklisted.
- We store only domain-level data (mail servers, outcome counts) and one-way hashes that cannot be turned back into addresses.
- For labelled checks, we store the signal numbers and the outcome, not the address.
- To allow feedback by email, we keep your latest check of each inbox for 14 days, under a one-way hash of the address.

## Next steps

- [Use the verdict](https://signupsieve.pages.dev/docs/verdicts): what to do with allow, review and block.
- [Endpoints](https://signupsieve.pages.dev/docs/endpoints): single, bulk, feedback and model stats.
- [Code examples](https://signupsieve.pages.dev/docs/examples): Node.js, Python, PHP, Next.js, Express and Laravel.
- [Pricing](https://signupsieve.pages.dev/pricing): from $0 a month.
- Download the [OpenAPI spec](https://signupsieve.pages.dev/openapi.yaml) or the [Postman collection](https://signupsieve.pages.dev/signupsieve-postman-collection.json).

## Sitemap

See the full [sitemap](https://signupsieve.pages.dev/sitemap.md) for all pages.