WRITE
AI writing engine
Subject lines, body, CTAs — in your voice, in seconds.
> LIVE OPTIMIZATION ENGINE
The email engine that tests itself.
Generate, split-test, and auto-scale winning email frameworks — for affiliate and performance teams who measure in EPC, not opens.
★★★★★ 4.9 · Trusted by 500+ marketing teams
Live optimization engine
> Brief:
Win-back coupon for dormant 90d list
Tone: friendly, urgency-led
Frameworks: PAS, BAB, Storytelling
Demo description
A simulated workflow showing the InboxEngine optimization engine: a campaign brief is sent, three copy variants are generated using PAS, BAB, and Storytelling frameworks, their open rates are measured, and the winner (Storytelling, 68% open rate) is selected with 100% of budget reallocated to it.
Trusted by performance teams at
Everything you need to scale.
InboxEngine combines generative AI with scientific split-testing to maximize ROI on every send.
TEST
Framework split-tester
AIDA vs. PAS vs. BAB, head-to-head. Auto-winner picked.
DELIVER
Inbox-first deliverability
Warm-up, sender reputation, and inbox-placement scoring built in.
MONETIZE
Offer-aware automations
Drop a ClickBank or JVZoo link; the engine routes the right offer per subscriber.
Stop guessing. Start testing.
InboxEngine doesn't just write emails — it pits copywriting frameworks against each other and shifts budget to the winner. Automatically.
- Test subject lines for maximum open rates
- Optimize CTAs for higher click-throughs
- Pit AIDA, PAS, BAB, and Storytelling head-to-head
- Automated winner selection and budget allocation
Active experimentSummer Launch 2026
Campaign performance · last 24h
Loading chart…
Total samples: 12,400Winner detected
Who's running this?
Built for the way performance teams actually work.
01Pick a framework. Engine writes 5 variants.
02Auto-tests on a small batch first.
03Scales the winner. Ship one campaign a day instead of one a week.
+38% open rate
$0.42 EPC
1.8x ROAS
Numbers, not testimonials.
What teams are actually shipping with InboxEngine.
+312% reply rate
“Switched from Mailchimp. The engine picked our winner before we knew it was a contender.”
[Author 1]
[Role] · [Company]
$2.41 EPC
“We A/B test 8 frameworks per campaign now. Used to be 2.”
[Author 2]
[Role] · [Company]
4.8x ROI
“Stopped guessing subject lines. Best decision of Q1.”
[Author 3]
[Role] · [Company]
Pay for what you use.
Credits cover every AI operation. Overage is automatic. No credit card to start.
Starter
$37/mo
Everything to ship your first split-tested campaign.
- 5,000 included credits / month
- 1 GB asset storage
- AI writing + split-testing
- Email + chat support
Pro
$97/mo
For teams scaling 10+ campaigns a week.
- 25,000 included credits / month
- 5 GB asset storage
- AI writing + split-testing
- Priority support
- Auto-budget reallocation
- API access
Agency
Custom
Multi-client switcher and white-label reporting.
- Volume credits
- Multi-client switcher
- White-label reporting
- Dedicated CSM
Overage at $0.01/credit · No credit card to start · See full pricing
Ready to engineer your inbox?
Free for 14 days. No credit card. Cancel in two clicks.