react-native-fake-email-guard

Lightweight, zero-dependency library to detect disposable and temporary email addresses. Works in React Native, React, and any JavaScript/TypeScript environment.

Bundles a curated blocklist of 500+ known disposable email providers (mailinator, tempmail, guerrillamail, yopmail, 10minutemail, trashmail, and hundreds more) — no network requests, works fully offline.

Installation

npm install react-native-fake-email-guard
# or
yarn add react-native-fake-email-guard

Usage

Basic check

import { isDisposableEmail, isFakeEmail, isValidEmail } from "react-native-fake-email-guard";

isDisposableEmail("[email protected]");  // true
isDisposableEmail("[email protected]");       // false

isFakeEmail("[email protected]");          // true  (alias)

isValidEmail("[email protected]");            // true  (format + not disposable)
isValidEmail("[email protected]");         // false
isValidEmail("notanemail");                // false

Detailed result

import { checkEmail } from "react-native-fake-email-guard";

const result = checkEmail("[email protected]");
// {
//   email: "[email protected]",
//   domain: "mailinator.com",
//   isDisposable: true
// }

Custom blocklist management

import { addBlockedDomains, removeBlockedDomains, resetBlocklist } from "react-native-fake-email-guard";

// Block additional domains specific to your use case
addBlockedDomains(["mycustomspam.io", "anotherfake.net"]);

// Whitelist a domain that's in the default blocklist
removeBlockedDomains(["mailinator.com"]);

// Restore the original default blocklist
resetBlocklist();

React Native Example

import React, { useState } from "react";
import { TextInput, Text, View, StyleSheet } from "react-native";
import { isDisposableEmail } from "react-native-fake-email-guard";

export function EmailInput() {
  const [email, setEmail] = useState("");
  const isInvalid = email.length > 0 && isDisposableEmail(email);

  return (
    <View>
      <TextInput
        value={email}
        onChangeText={setEmail}
        placeholder="Enter your email"
        autoCapitalize="none"
        keyboardType="email-address"
        style={[styles.input, isInvalid && styles.inputError]}
      />
      {isInvalid && (
        <Text style={styles.errorText}>
          Temporary email addresses are not allowed.
        </Text>
      )}
    </View>
  );
}

const styles = StyleSheet.create({
  input: {
    borderWidth: 1,
    borderColor: "#ccc",
    borderRadius: 8,
    padding: 12,
  },
  inputError: {
    borderColor: "#e53e3e",
  },
  errorText: {
    color: "#e53e3e",
    fontSize: 12,
    marginTop: 4,
  },
});

API

| Function | Signature | Description | |---|---|---| | isDisposableEmail | (email: string) => boolean | Returns true if the domain is a known disposable provider | | isFakeEmail | (email: string) => boolean | Alias for isDisposableEmail | | isValidEmail | (email: string) => boolean | Returns true if the email is well-formed AND not disposable | | checkEmail | (email: string) => EmailCheckResult | Returns a detailed result object | | addBlockedDomains | (domains: string[]) => void | Add custom domains to the blocklist | | removeBlockedDomains | (domains: string[]) => void | Remove domains from the blocklist (whitelist) | | getBlockedDomains | () => string[] | Returns all currently blocked domains | | resetBlocklist | () => void | Resets to the built-in default blocklist |

EmailCheckResult type

interface EmailCheckResult {
  email: string;
  domain: string;
  isDisposable: boolean;
}

Notes

• All comparisons are case-insensitive
• No network requests — detection is 100% offline
• Blocklist changes via addBlockedDomains / removeBlockedDomains persist for the lifetime of the module
• Fully typed — ships with TypeScript definitions out of the box

License

MIT