If you have spent any time validating B2B email lists, you have probably tried Emailable. It is fast, the dashboard is clean, and the pricing is approachable. For consumer lists and low-stakes newsletters, it does the job.
The problem shows up the moment you point it at a real B2B prospecting list. A large slice of your most valuable contacts come back marked “unknown” or “risky,” and you are left guessing whether to send. Those unknowns are almost always catch-all domains, and catch-all domains are exactly where most B2B buyers sit.
This post breaks down where Emailable is strong, where it leaves you stuck, and why teams running serious outbound move to Scrubby when accuracy on hard-to-verify addresses starts costing them meetings.
What Emailable Does Well
Credit where it is due. Emailable handles the easy cases competently:
- Syntax and format checks. It catches typos, malformed addresses, and obvious junk before they ever hit your sender reputation.
- Known-bad domain filtering. Disposable domains, role accounts, and dead mailboxes get flagged reliably.
- Speed at volume. Bulk uploads process quickly, and the API is responsive enough for real-time form validation.
If your list is mostly Gmail, Outlook, Yahoo, and other major consumer providers, Emailable will verify the overwhelming majority of it with confidence. For that use case, it is a fine tool.
Where It Falls Short: The Catch-All Problem
A catch-all (or accept-all) domain is configured to accept mail for any address at that domain, valid or not, without bouncing at the SMTP layer. Most standard validators, Emailable included, cannot tell whether a specific mailbox behind a catch-all actually exists. So they hedge and return “unknown,” “accept-all,” or “risky.”
Here is why that matters: a huge portion of B2B companies run catch-all configurations. When your validator punts on every one of them, you are left with two bad options:
- Skip the unknowns and quietly delete a third or more of your best prospects.
- Send to them anyway and gamble with your bounce rate and domain reputation.
Neither is acceptable when each contact represents a real revenue opportunity. The whole point of validation is to remove the guesswork, not relocate it.
How Scrubby Handles What Emailable Cannot
Scrubby was built specifically to resolve the catch-all addresses that other tools give up on. Instead of stopping at the SMTP handshake, it uses deeper verification techniques to determine whether a mailbox behind a catch-all domain is genuinely live.
The practical difference looks like this:
| Scenario | Typical Emailable result | Scrubby result |
|---|---|---|
| Consumer mailbox (Gmail, Outlook) | Valid | Valid |
| Disposable or role address | Invalid / flagged | Invalid / flagged |
| Catch-all B2B domain | Unknown / risky | Valid or invalid (resolved) |
That last row is the entire reason teams switch. When Scrubby returns a verdict on catch-all addresses, you recover prospects that would otherwise sit in an “unknown” bucket forever, and you send with confidence instead of crossing your fingers.
When Switching Is Worth It
You do not need to switch tools for the sake of it. Stay with Emailable if your lists are mostly consumer addresses and your unknown rate is already low.
Move to Scrubby if any of these describe you:
- A meaningful share of your list comes back “unknown” or “accept-all.”
- You run B2B outbound where catch-all domains are the norm, not the exception.
- Your sales team is manually re-checking risky addresses, wasting hours every week.
- Bounce rates are creeping up and threatening inbox placement on your cold campaigns.
If you are running cold outreach at volume, clean validation is only half the battle. Once your list is verified, the channel you use to reach people still decides whether you book the meeting. Many of our customers pair a validated list with calendar-invite outreach through Kali to get in front of prospects who ignore traditional cold email entirely.
The Bottom Line
Emailable is a solid validator for straightforward lists. But “unknown” is not an answer when you are spending real money to build a pipeline, and catch-all domains are where the modern B2B buyer lives.
Scrubby exists to turn those unknowns into clear, actionable verdicts so you keep more of your real prospects and protect your sender reputation at the same time. If catch-all addresses are the reason your validation feels unfinished, run a sample list through Scrubby and compare the resolved rate side by side. The difference is usually obvious within the first upload.
Nick Abraham
Cold Email Expert