Marketing
Your email list is decaying. Know exactly where and what to do about it.
Weekly audit of subscriber engagement, list growth, and deliverability across Mailchimp and Kit. Inactive segments, broken links, and bounce buildup are flagged with projected impact so problems get fixed before open rates crater.
What changes
Time to identify issues
Months (noticed only when open rates visibly drop)
Weekly, with trend alerts for gradual declines
List health visibility
Aggregate open rate is the only signal
Inactive count, bounce rate, spam complaints, and link health tracked per segment
Deliverability risk detection
Discovered after emails start landing in spam
Spam complaint rate and bounce buildup flagged before threshold is crossed
Broken link detection
Found by subscribers (if they report it)
Every link in active sequences validated weekly
Your email list decays silently until deliverability tanks
You have 45,000 subscribers across Mailchimp (newsletter) and Kit (course sequences). Open rates have dropped from 28% to 19% over 6 months. You're not sure if it's content, timing, or list quality. Nobody has cleaned the list in a year. 8,000 subscribers haven't opened an email in 90+ days, but they're still getting every send, dragging your engagement metrics down and training spam filters that you're sending unwanted email.
The Kit welcome sequence has a 52% open rate on email 1 and a 9% open rate on email 5. The drop-off is normal, but email 3 has a broken link that's been there for 4 months. 2,400 subscribers clicked a dead link and got a 404. Nobody reported it because the analytics only show "clicked" without checking the destination.
How ZeroTwo monitors your email health
Pulls subscriber engagement, bounce data, and campaign metrics
Mailchimp32,000 subscribers. Open rate trend: 28% to 19% over 6 months. 8,200 subscribers with zero opens in 90+ days. 1,400 hard bounces not yet cleaned. Last 4 campaigns averaged 19.1% open rate, down from 22.4% the month before. Spam complaint rate: 0.08% (approaching the 0.1% threshold).
Pulls sequence performance and link health across active automations
Kit13,000 subscribers across 3 sequences. Welcome sequence: 52% open on email 1, 9% on email 5. Email 3 has a link with 2,400 clicks but the destination returns a 404. Course upsell sequence converting at 1.2%, down from 2.8% last quarter.
Identifies actions ranked by deliverability impact
Google4 actions ranked by deliverability impact: sunset 8,200 inactive Mailchimp subscribers (projected open rate improvement to 24%), clean 1,400 hard bounces (spam complaint rate drops to 0.05%), fix broken link in Kit email 3, and investigate course upsell conversion decline (pricing page redesigned last quarter, likely cause). Projected inbox placement improvement from list cleaning: 3-5 points.
Get started in under 10 minutes
Connect your tools
One-click OAuth for each integration. No API keys, no engineering.
Describe what you need
“Audit our Mailchimp newsletter and Kit sequences every week. Flag subscribers with zero opens in 90+ days, hard bounces not yet removed, spam complaint rate approaching 0.1%, and any links in active sequences returning non-200 status codes. Rank actions by deliverability impact.”
It runs on schedule
List health report delivered every Monday.
Frequently asked questions
ZeroTwo recommends removals and shows the projected impact on open rates and deliverability. You approve the action before any subscribers are removed. ZeroTwo can also create a re-engagement segment so you can send a final "are you still interested?" email before sunsetting.
ZeroTwo extracts every URL from your active sequences and checks the HTTP response code. Links returning 404, 500, or redirect loops are flagged with the specific email and step number so you can fix them immediately.
ZeroTwo also connects to Klaviyo, Sendgrid, and Resend. If your email platform has a reporting API, ZeroTwo can pull engagement and deliverability data from it. The audit logic is the same regardless of platform.
By default, subscribers with zero opens in 90 days. You can adjust this threshold during setup. Some teams use 60 days for high-frequency sends or 120 days for monthly newsletters. ZeroTwo adapts the inactive definition to your sending cadence.
ZeroTwo tracks your spam complaint rate per campaign and as a rolling average. Most email providers start throttling or blocking at 0.1%. ZeroTwo alerts you when you cross 0.05% so you have time to act before reaching the danger zone.
Yes. ZeroTwo maps open rates, click rates, and unsubscribe rates for every email in each sequence. Drop-off between steps is expected, but ZeroTwo flags steps where the decline is steeper than normal or where unsubscribe rates spike.
Related workflows
- MarketingRevenue Attribution by Flow
- MarketingCross-Channel Performance
- Ops & Chief of StaffTransactional Email Watchdog
Stop doing the work your tools should do for you.
Set it up once. ZeroTwo runs it every time.