Stop Guessing Which Subject Line Actually Works
SubjectSplit connects to your email platform, automatically splits your audience, tests subject line variants, and surfaces the winner — all before your next send.
Start Optimizing — $12/moWorks with Mailchimp, ConvertKit, Beehiiv & more. Cancel anytime.
+34%
avg open rate lift
2 min
setup time
Real-time
winner detection
Pro Plan
$12
per month · cancel anytime
- ✓Unlimited A/B tests
- ✓Connect up to 3 email platforms
- ✓Real-time open rate dashboard
- ✓Automatic winner selection
- ✓Webhook-based integration
- ✓Email support
Frequently Asked Questions
Which email platforms are supported?
SubjectSplit integrates with Mailchimp, ConvertKit, Beehiiv, and ActiveCampaign via their official APIs and webhooks. More platforms are added regularly.
How does the automatic winner selection work?
We monitor open rates in real time. Once a variant reaches statistical significance, SubjectSplit automatically flags the winner and can trigger the winning send to the remainder of your list.
Can I cancel my subscription at any time?
Yes. Cancel from your billing portal with one click. You keep access until the end of your billing period with no questions asked.