Emailens
Email Clients

Email Clients

Overview of the 13 email clients Emailens supports and their rendering characteristics.

Emailens simulates rendering across 13 email clients spanning webmail, desktop, and mobile platforms.

Client list

ClientIDCategoryEngineDark modeNotes
Gmailgmail-webWebmailGmail WebYes
Gmail Androidgmail-androidMobileGmail MobileYes
Gmail iOSgmail-iosMobileGmail MobileYes
Outlook 365outlook-webWebmailOutlook WebYes
Outlook (New)outlook-windowsDesktopOutlook WebYesReplaces classic Outlook
Outlook Classicoutlook-windows-legacyDesktopMicrosoft WordYes⚠️ EOL Oct 2026
Apple Mailapple-mail-macosDesktopWebKitYes
Apple Mail iOSapple-mail-iosMobileWebKitYes
Yahoo Mailyahoo-mailWebmailYahooYes
Samsung Mailsamsung-mailMobileSamsungYes
ThunderbirdthunderbirdDesktopGeckoYes
HEY Mailhey-mailWebmailWebKitYes
SuperhumansuperhumanDesktopBlinkYes

Rendering engines

Different email clients use different rendering engines, which determines their CSS support:

  • Gmail Web/Mobile — proprietary engine that strips <style> blocks, forces inline styles, and removes many modern CSS features
  • Microsoft Word — Outlook Classic (legacy) uses Word to render HTML, severely limiting CSS support. Reaching EOL October 2026.
  • Outlook Web — browser-based engine used by Outlook.com, Outlook 365, and the new Outlook for Windows. Good CSS support.
  • WebKit — Apple Mail uses Safari's engine, supporting most modern CSS
  • Gecko — Thunderbird uses Firefox's engine with excellent CSS support
  • Yahoo — proprietary engine with moderate CSS support
  • Samsung — proprietary mobile engine
  • WebKit (HEY) — HEY Mail uses WebKit with excellent CSS support
  • Blink (Superhuman) — Superhuman uses Chrome's Blink engine with excellent CSS support

Accessing client data

import { EMAIL_CLIENTS, getClient } from "@emailens/engine";

// All clients
console.log(EMAIL_CLIENTS.length); // 13

// Single client
const newOutlook = getClient("outlook-windows");
console.log(newOutlook?.engine); // "Outlook Web"

const legacyOutlook = getClient("outlook-windows-legacy");
console.log(legacyOutlook?.engine); // "Microsoft Word"
console.log(legacyOutlook?.deprecated); // "2026-10"

On this page