Watching bounce rates climb. Seeing open rates drop. Wondering why emails that used to land in inboxes now disappear into spam. We built BounceShift because we lived that nightmare—and found a way out.
It started with a product launch that almost didn't happen.
Back in 2023, we were preparing to announce a major feature update to our 47,000-person email list. The campaign was ready. The landing page was live. We hit send.
Within hours, our bounce rate hit 8.4%. Our sender score tanked. Gmail started routing our emails straight to spam—not just for that campaign, but for everything we sent afterward.
Three months. That's how long it took to rebuild our sender reputation.
Three months of reduced revenue, frustrated customers who weren't getting our emails, and a support team fielding "I never got your email" tickets.
We learned two things from that experience:
So we built the tool we wished we had.
Most teams discover bad emails after they've already hurt their sender reputation. We built BounceShift to catch invalid addresses at the point of entry—in signup forms, during imports, before campaigns go out.
Email addresses in our reputation database are stored as one-way cryptographic hashes. We literally cannot read, export, or sell them—the original addresses don't exist in our system. Your validation data is processed, then deleted.
No monthly minimums. No expiring credits. No surprise overages. You buy credits, you use them when you need them. Simple.
Our API docs aren't an afterthought. They're written by the engineers who built the API, with real examples, clear error messages, and code snippets that actually work.
We're a small team that's spent years in the email trenches—building ESPs, debugging deliverability issues, and helping companies recover from sender reputation disasters.
We're not trying to build the next unicorn. We're trying to build the most reliable, most developer-friendly email validation service on the market. The kind of tool we'd want to use ourselves.
Buy what you need. Use it when you need it. No "use it or lose it" pressure.
Connect Mailgun, SendGrid, Postmark, or SES. We automatically track bounces and complaints to build your reputation database over time.
We don't just check syntax. We verify MX records, validate SMTP responses, detect disposable domains, identify catch-all servers, and flag role-based addresses.
Manage API keys, track usage by project, and control permissions across your organization.
Start with 100 free validations. No credit card required.