Email Marketing Tools with A/B Testing
If A/B testing is one of the main features you care about, the question is not just whether a platform has split testing. The real differences are what you can test, how easy the workflow is, and whether the tool is good enough overall for the rest of your email program.
Why A/B Testing Matters
Small improvements in open rates and click-through rates compound over time. A/B testing lets you make data-driven decisions about subject lines, content, and send times instead of relying on guesswork.
What We Looked For
We looked for platforms that support testing at least subject lines and email content, with automatic winner selection based on performance metrics.
42 Tools with A/B Testing
Instantly.ai
Cold email at scale with unlimited accounts and AI-powered warmup
Instantly.ai is a cold email platform built for volume, offering unlimited email accounts, AI-powered warmup, and inbox rotation to maximize deliverab...
Moosend
All-in-one email marketing and automation
Moosend is a budget-friendly email marketing platform that punches above its weight class. Despite its low price point, it offers solid automation, tr...
EngageBay
All-in-one CRM for marketing, sales & support
EngageBay is a bootstrapped all-in-one CRM platform that bundles marketing automation, sales pipeline management, helpdesk ticketing, and live chat in...
Apollo.io
Sales intelligence platform with 210M+ contacts and built-in outreach
Apollo.io is the leading sales intelligence platform with a 210M+ contact database, built-in email sequences, dialer, and meeting scheduler. It earned...
Kit (ConvertKit)
Email marketing built for creators
Kit (formerly ConvertKit) is purpose-built for online creators including bloggers, podcasters, YouTubers, and course creators. It emphasizes simplicit...
MailerLite
Email marketing tools for growing businesses
MailerLite is known for its simplicity, affordability, and clean design. It's one of the best options for small businesses and beginners who want prof...
Klaviyo
The platform for unified customer data
Klaviyo is the gold standard for ecommerce email and SMS marketing, particularly for Shopify stores. Its deep integration with ecommerce platforms ena...
Omnisend
Ecommerce email and SMS made easy
Omnisend is an ecommerce-focused marketing platform that combines email, SMS, and web push notifications. It offers pre-built automation workflows for...
tinyEmail
AI-powered email marketing built for Shopify stores
tinyEmail is an AI-powered email marketing platform purpose-built for Shopify and e-commerce stores, offering an unusually affordable volume-based pri...
Reply.io
AI-powered sales engagement across email, LinkedIn, calls, and SMS
Reply.io is an AI-powered sales engagement platform that unifies email, LinkedIn, calls, SMS, and WhatsApp into multichannel sequences for B2B outreac...
Smartlead
Unlimited mailboxes and warmup for cold email at scale
Smartlead is a cold email infrastructure platform built for agencies and high-volume senders, offering unlimited email accounts and warmup on every pl...
Privy
Ecommerce email and SMS marketing built for Shopify stores
Privy is an ecommerce-focused email and SMS marketing platform built specifically for Shopify stores, combining conversion popups, email campaigns, an...
ActiveCampaign
Marketing automation that drives growth
ActiveCampaign is widely regarded as having the best marketing automation capabilities in the email marketing space. It combines email marketing with ...
Brevo (Sendinblue)
The most approachable CRM suite
Brevo (formerly Sendinblue) stands out with its unique pricing model based on email volume rather than subscriber count. This makes it particularly at...
beehiiv
The newsletter platform built for growth
beehiiv was built by the team behind Morning Brew's growth to 4 million subscribers. It's specifically designed for newsletter businesses with built-i...
Lemlist
Multichannel cold outreach with built-in email warmup and lead database
Lemlist is a multichannel cold outreach platform that combines email campaigns, LinkedIn automation, and cold calling with a built-in 450M+ lead datab...
Woodpecker
B2B cold email tool with deliverability-first approach
Woodpecker is a B2B cold email tool founded in 2015 that takes a deliverability-first approach with built-in warmup, catch-all verification, and bounc...
Mailmodo
Interactive AMP email marketing with in-email forms and surveys
Mailmodo is the pioneering interactive email marketing platform that uses AMP technology to let recipients fill forms, take surveys, book meetings, an...
ConvertFlow
All-in-one conversion platform with personalized popups, forms, and landing pages
ConvertFlow is an all-in-one conversion platform that combines personalized popups, multi-step forms, landing pages, quizzes, and sticky bars to conve...
Drip
Marketing automation for ecommerce
Drip is a focused ecommerce marketing platform known for its powerful visual automation builder and behavior-based segmentation. It's designed specifi...
HubSpot Email Marketing
Email marketing powered by CRM data
HubSpot's email marketing is part of its complete Marketing Hub. While the free and Starter tiers offer competitive email marketing, the real power co...
Elastic Email
Budget-friendly email delivery with marketing features
Elastic Email is a budget-friendly email delivery platform founded in 2010 that offers both transactional email API and marketing email capabilities. ...
Customer.io
Behavioral messaging platform for product-led SaaS and tech companies
Customer.io is a behavioral messaging platform built for product-led SaaS companies that need to trigger automated emails, SMS, push notifications, an...
Ortto
All-in-one CDP, marketing automation, and analytics platform for lifecycle marketing
Ortto (formerly Autopilot) is an all-in-one marketing platform that combines a Customer Data Platform, visual journey-based automation, and built-in a...
Braze
Rewrite the rules of customer engagement with AI
Braze is a leading enterprise customer engagement platform that enables brands to orchestrate personalized, cross-channel experiences at massive scale...
GetResponse
All-in-one marketing platform
GetResponse is a full-featured marketing platform that goes beyond email marketing to include webinars, landing pages, sales funnels, and marketing au...
Mailchimp
Turn emails into revenue
Mailchimp is the most widely recognized email marketing platform, used by millions of businesses worldwide. Acquired by Intuit in 2021, it offers a fu...
Zoho Campaigns
Affordable email marketing deeply integrated with the Zoho ecosystem
Zoho Campaigns is the email marketing arm of the Zoho ecosystem, launched in 2012 and designed to work directly with Zoho CRM, Zoho One, and 45+ other...
Benchmark Email
Straightforward email marketing with all features on every plan
Benchmark Email is a multilingual email marketing platform founded in 2004 that takes an all-features-included approach, giving every user access to a...
Iterable
Campaigns are out. Moments are in.
Iterable is an AI-powered cross-channel marketing platform that helps brands create individualized customer experiences across email, SMS, push, in-ap...
AWeber
Powerfully simple email marketing
AWeber is one of the original email marketing platforms, serving small businesses since 1998. It offers the largest template library (600+) and an imp...
Keap
CRM-powered sales and marketing automation for small businesses
Keap (formerly Infusionsoft, founded 2001, acquired by Thryv in 2024) is a premium all-in-one CRM and marketing automation platform built for sales-dr...
MailerSend
Developer-friendly transactional email by the MailerLite team
MailerSend is a transactional email service built by the team behind MailerLite, launched in 2020 with over a decade of email deliverability expertise...
Constant Contact
Small business marketing made easy
Constant Contact is one of the most established email marketing platforms, particularly strong for small businesses and nonprofits. Its event marketin...
Campaign Monitor
Beautifully crafted email marketing
Campaign Monitor is particularly well-suited for agencies and brands that need polished, branded email campaigns. Its client management features and b...
Encharge
Email & marketing automation, simplified
Encharge is a marketing automation platform built for SaaS and product-led companies. It excels at behavior-based email sequences triggered by in-app ...
Salesforce Marketing Cloud
Personalize every moment with the #1 AI CRM for marketing
Salesforce Marketing Cloud is the enterprise marketing automation suite within the Salesforce ecosystem, offering email, SMS, social, advertising, and...
Twilio SendGrid
Scalable email API trusted by developers worldwide
Twilio SendGrid is a cloud-based email delivery platform founded in 2009 and acquired by Twilio for $2 billion in 2019. It uniquely splits its offerin...
Mailjet
Collaborative email platform for teams with powerful API
Mailjet is a French-founded email platform (now owned by Sinch) that uniquely combines transactional and marketing email under one roof with real-time...
Vero
Make every email, SMS, push count
Vero is a multi-channel customer engagement platform for product-led teams that need behavioral messaging. It enables personalized emails, push notifi...
Maropost
Unified commerce platform that connects every channel
Maropost is a unified commerce and marketing automation platform for mid-market ecommerce businesses. It combines email, SMS, social advertising, and ...
Venturz
Your all-in-one platform to build a successful startup
Venturz is an all-in-one startup platform that bundles website building, CRM, email marketing, community management, and helpdesk into a single subscr...
Frequently Asked Questions
What should I A/B test first in my email campaigns? +
Start with subject lines since they have the biggest impact on open rates. Once you have a baseline, test preheader text, send times, CTA button copy, and email layout.
How large does my email list need to be for A/B testing? +
You typically need at least 1,000 subscribers per variant to get statistically meaningful results. With smaller lists, focus on testing high-impact elements like subject lines.
What is multivariate testing in email marketing? +
Multivariate testing lets you test multiple variables simultaneously, like subject line and sender name together. It requires larger lists but reveals how different elements interact with each other.
How long should I run an A/B test before picking a winner? +
Most platforms wait 1-4 hours for sufficient data before automatically sending the winning version to the rest of your list. For smaller lists, waiting 12-24 hours gives more reliable results.