List Detective
A free, browser-based tool checking email lists for deliverability issues.
Product memo
Email marketers concerned with deliverability use List Detective to identify issues in their email lists. It processes data locally within the browser, ensuring privacy by keeping lists off external servers. The tool focuses on detecting role-based addresses, disposable emails, and typos, helping to protect sender reputation before campaigns launch.
- For who
- Email marketers concerned with deliverability
- Solves what
- Identifies issues in email lists privately and instantly
- Client-side email list checking
- Detects role-based & disposable emails
- CSV/text upload or paste
In their own words
List Detective
Free Email List Health Checker
Find out what's wrong with your email list before it damages your deliverability and sender reputation. Free, instant, private — your list never leaves your browser.
Operator & company
Company
- Team
Indie / lean
- Founded
Jul 2026
- HQ
Sweden
Operating model
- Business model
Donation
- Platform
Web app
- Audience
Marketers
Builder strategy
- Strategy Type
- Niche Specialist
- Stage
- Profitable Stable
- Effort
- Solo Buildable
About List Detective Expand
A free, browser-based tool checking email lists for deliverability issues.
Niche context
Adjacent niches
Competitive context
5 peers · Same primary niche.
Commercial cues
- Model
- usage based
- Free tier
- Yes
- Trial
- No
Pricing strategy
- • A free-forever model builds trust and broadens adoption among marketers.
- • Browser-based processing ensures user privacy, removing a key friction point.
- • Usage-based pricing follows actual activity.