clean-validate

Clean & Validate — Sub-Skill

You help users verify email and phone data, manage bounce rates below 1%, and establish list hygiene schedules. Always read the reference file before responding.

Reference

Read {SKILL_BASE}/resources/data-validation.md — all sections.

Email Verification Tools

Tool	Cost	Accuracy	Best For
ZeroBounce	$0.008/email	98%+	High-volume, agencies
NeverBounce	$0.008/email	99.9%	Bulk verification
Findymail	$49/mo (1K)	97%+	Find + verify combined
MillionVerifier	$37/10K	99%+	High volume, low cost
Bouncer	$8/1K	99.5%	EU compliance focus

Verification Result Categories

Category	Action
Valid/Deliverable	Safe to send (target: 95%+ of list)
Invalid/Undeliverable	Remove immediately
Risky/Accept-All (Catch-all)	Send cautiously or find alternative. Use ListKit/Listman.io for catch-all sub-verification
Unknown	Treat as risky, do not send
Disposable	Remove (temporary email)
Role-based (info@, sales@)	Remove — higher spam complaint risk
Toxic/Spam Trap	Remove immediately

Critical Metrics

Metric	Target	Danger Zone
Bounce rate	<1%	>3% = pause campaigns immediately
Spam complaint rate	<0.1%	>0.3% = investigate
Email deliverability	95%+	<90% = infrastructure issue

Data Decay Rates

• Email addresses — 22-30% annual decay (~2.1%/month)
• Phone numbers — 15-20% annual decay
• Job titles — 30-35% annual decay
• Company employment — 20-25% annual decay

List Hygiene Schedule

Frequency	Action
Before every campaign	Full email verification on entire list
Weekly	Monitor bounce rates, remove hard bounces
Monthly	Re-verify risky and catch-all emails
Quarterly	Full re-verification, update job titles, purge unengaged (no opens/clicks 90 days)
Bi-annually	Complete data refresh from LinkedIn, re-verify all
Annually	Full ICP audit, rebuild lists from scratch

Rule: Re-verify any list older than 30 days before sending.

Bounce Handling Workflow

Email Sent -> Delivered -> Track engagement
           -> Soft Bounce -> Retry 3x (4h, 24h, 48h) -> Still bouncing? -> Hard Bounce
           -> Hard Bounce -> Remove IMMEDIATELY -> Add to suppression list -> Flag source for quality review

Examples

Example 1: "My bounce rate is 4%, what do I do?" -> Pause all campaigns immediately (>3% = danger zone). Run full re-verification on entire list with ZeroBounce or NeverBounce. Remove all Invalid, Unknown, Disposable, Toxic. Sub-verify catch-all emails with ListKit. Check data sources — flag and potentially stop using the source with highest bounce rate. Target: get back below 1% before resuming.

Example 2: "Which email verification tool should I use?" -> Volume-based: <1K/month = Findymail ($49, finds + verifies). 1K-10K/month = NeverBounce ($0.008/email, 99.9% guarantee). 10K+/month = MillionVerifier ($37/10K, best cost). EU-focused = Bouncer or Dropcontact (GDPR-compliant). Catch-all heavy = add ListKit/Listman.io as secondary verification.

Example 3: "How often should I clean my list?" -> Verify 100% before every campaign, no exceptions. Weekly: remove hard bounces. Monthly: re-verify catch-all and risky. Quarterly: full refresh + purge unengaged. Email decays 22-30%/year, so a list from 6 months ago has ~11-15% bad data. Re-verify anything older than 30 days.

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