Best Singleton UI Kit Alternatives & Competitors in 2025

Responsive HTML email templates for startups

Test your HTML emails before sending them

The #1 email warming service to improve your deliverability by generating realistic and meaningful engagement to your emails. Easy-to-use solution to help you land in the main inbox instead of the spam folder.

Visit website paid $19.5 / Monthly (Pro)

The open source framework for responsive emails

Open Source

MailChimp is the best way to design, send, and share email newsletters.

Responsive newsletters and email templates 💌

Email marketing for marketers, entrepreneurs, and eCommerce

Create, edit and manage awesome email newsletters 😻

Hundreds of free, responsive email templates. Pick and edit.

Klaviyo helps brands own the customer experience, grow higher-value relationships, and deliver more personalized marketing experiences across email, mobile, and web.

Bee is MailUp's drag-&-drop editor for responsive design emails.

Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.

Design and create beautiful HTML emails and templates in any way you want with Chamaileon's collaborative email template builder platform. You can create nice emails in no time without coding. You can optimize email production to save time & effort.

paid Free Trial $125.0 / Monthly (5 users included. Unlimited exports and test emails.)

Responsive HTML email templates for startups & developers