The best way to check a misspelled email address in JavaScript

? Reduce failed authentication      ⬆️ Increase emails delivery      ⚡️ Built for speed

Did you say? The best email spell checker in JavaScript


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EmailSpellChecker is a lightweight JavaScript module written in TypeScript that suggests the right domain when your users misspell it in an email address.

At ZooTools – web3 Mailchimp alternative, we validate thousands of misspelled emails daily with EmailSpellChecker and it helped us to reduce bounced emails by 30%.

It’s by far the easiest way to reduce misspelled email addresses in your web apps and server.

The features your deserve

We rewrote and improved mailcheck.js, a great module that is no longer maintained (7+ years since the last update) and we fixed critical bugs like this, or this.

  • ⚡️ Lighting fast: Highly performance email checking using Sift3 – a fast and accurate string distance algorithm.
  • ? Updated: 39+ popular domains, and 66+ modern TLDs out-of-the-box. Frequently updated.
  • ? Ridiculously small: 1.8KB (minzip) and 0 external dependencies. We agree, big bundles suck!
  • ? TypeScript: Fully written in TypeScript, cause we know you love it and we too.
  • ⚙️ Extensible: Allows you to pass your custom rules and domains. Tweak it as you need.
  • ? 1-minute migration: Same API and functions as mailcheck so you can switch in a sec!
  • ? Unit tested: Cause we’d not ever used a library without tests :).

Why should you validate email spelling?

Typos in the email will harm your business. Especially email deliverability. Common user misspellings such as “gnail” instead of “gmail” or “yaho” instead of “yahoo” can be used as spam traps by ISPs, and as a result, your emails will be blocked or marked as spam.

Common use cases:

  • User authentication (login, signup, email recovery).
  • Backend email validation.
  • Newsletter subscriptions.


Here are some highly-requested tutorials.

If you want to write a tutorial send a PR or create an issue if you want to ask for one.

Getting Started in 5 minutes

Adding EmailSpellChecker to your project takes less than 5 minutes.

It works on any JavaScript framework (Vue, React, Next.JS, Angular, Svelte, etc) as well as your backend server.


Install with npm:

npm i @zootools/email-spell-checker --save

Install with yarn:

yarn add @zootools/email-spell-checker

Basic Example

Using the library is really easy:

  • Import it.
  • Call run function with the email you want to validate.
  • Get the suggested email, and prompt your user to accept the suggestion.

import emailSpellChecker from '@zootools/email-spell-checker';

const suggestedEmail ={
  email: '[email protected]',

if (suggestedEmail) {
  // DEV: Handle the suggestion.
  // E.g: tell the user their email is wrong and offer to apply your suggestion

  // {
  //    address: "jorge"
  //    domain: ""
  //    suggestedEmail: "[email protected]"
  // }

Extending Domains

EmailSpellChecker has inbuilt defaults if the domains, secondLevelDomains or topLevelDomains options aren’t provided.

The out-of-the-box configuration is the best for 99% of cases. If you are that 1%, here is how you can extend the configuration :).

Adding your own Domains

You can replace EmailSpellChecker’s default domain/TLD suggestions by supplying replacements to{
  domains: [...emailSpellChecker.POPULAR_DOMAINS, ''], // replaces existing domains
  secondLevelDomains: ['domain', 'yetanotherdomain'], // replaces existing SLDs
  topLevelDomains: ['', 'ru'], // replaces existing TLDs


EmailSpellChecker is tested with Jest, a popular JavaScript testing framework from Facebook with a focus on simplicity.

Run npm test from the command line to run the test suite.

Who uses EmailSpellChecker?

We’re putting together a list of happy users of EmailSpellChecker.

Tweet us @ZooToolsHQ and @JGFerreiro if you are interested to appear.

Customer support & updates


Customer support



This library is used and maintained by ZooTools: Growth and marketing tools for ambitious teams.

We use this library heavily in ZooTools Panda, a mailchimp alternative for sending viral marketing campaigns.

You can view examples of the use of this library here

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