Make unknown senders work to get into your inbox.
Stop AI cold spam
Make unknown senders work to get into your inbox.
Stop AI spam from flooding your inbox and calendar. Unknown senders solve a CAPTCHA or pay a fee to get in. Trusted contacts get through as usual.
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Trusted284
InboxArchived 2Trusted 284
SC
Sarah Chen
now
sarah@designco.com
Re: new design direction
Checking sender…Delivered to your inbox
Inbox · just delivered
3 items
- SC Sarah Chen Re: new design direction now
- S Stripe Receipt for your subscription 6m
- L Linear PR #842 was merged 1h
- Real-time inbox filtering
- Calendar invite protection
- Trusted circle from sent history
- Introduction detection via CC
- Configurable filter rules
- Custom auto-reply templates
- Emails archived, never deleted
Sarah
Verified sender
2 awaiting verification
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Built for inboxes overwhelmed by AI outreach
AI cold outreach is nearly free.
Make senders work for your time and attention.Spam filters catch the obvious, but mass-customized outreach gets through. You miss what matters and drown in what you didn't ask for.
Step 01
Sign in with your email provider.
Captchainbox scans your conversation metadata. We never read your messages. We build a trusted sender and domains list for you.
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you@gmail.com
Scanning sent history…0%
Analyzed
2,847
Trusted
284
Status
Active
Step 02
Every sender checked silently.
For every new email Captchainbox checks the sender against your trusted contacts. Unknown senders are archived (never deleted) and sent a verification link. Introductions through trusted contacts get through.
Inbox protection
Live
Step 03
Senders show they are worth your time and attention.
Unknown senders verify through a CAPTCHA or pay a small fee to show they are relevant to you. They complete the verification and their email is delivered to your inbox. Payment fees get pooled and donated.
See the verification flow in action
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Pricing
Simple pricing to get back your time and attention.
Free 7-day trial, no credit card required.
Per inbox
$5/ month
7-day free trial included
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