Verify a Cold Email List in two minutes
Cold outreach operates at the boundary of permission: you are mailing people who did not explicitly opt in, which means every technical failure — a hard bounce, a spam trap hit, a complaint — carries more reputational weight than it would in a warm list context. Verifying cold email lists before sequencing them is not optional hygiene; it is the difference between a campaign that gets delivered and one that causes your sending domain to be blacklisted before the first reply comes in. The stakes are especially high for newly warmed domains with little reputation buffer.
What's hiding in your list
Prospecting tools and data providers do not verify deliverability at the time of export — a list from even a reputable provider can contain 10–20% invalid addresses by the time you load it into your sequencer.
Cold lists built from scraped or enriched sources have a higher incidence of catch-all domains, where SMTP will accept any address whether or not a real mailbox exists behind it.
Sending high volumes of cold email from a new domain before it is fully warmed amplifies the damage from bounces, since there is no positive engagement history to offset the negative signals.
Email and phone — cleaned in one pass
Verify in one pass
Every email checked for deliverability and every phone validated — in a single upload.
Catch what others miss
Typos, catch-all domains, disposable addresses, dead numbers and silent duplicates.
Flat, simple pricing
Warm up safely with a verified list. No per-credit math, no surprise overage bills.
Clean leads in three steps
No setup, no integrations, no learning curve. Upload a file, download a better one.
Upload your CSV
Drag in any contact list. We auto-detect email, phone, name and company columns.
We verify everything
Every email checked for deliverability, every phone validated, duplicates flagged — with a live quality score.
Download clean leads
Export a verified, deduplicated list your team can actually call and email.
Email and phone, cleaned in a single upload — see exactly how many bad contacts are hiding in your list before you pay a cent.
100 free verifications · no credit card · results in under 2 minutes
Frequently asked
Can I verify a cold prospect list before importing it into my sequencer?
Yes — upload the CSV, let verification run, filter out invalid and high-risk addresses, then import the cleaned file; most sequencers accept the same CSV format BounceBlock exports.
How should I treat catch-all addresses in a cold outreach context?
For cold outreach, the conservative approach is to suppress catch-all addresses or move them to a separate low-volume sequence — the risk of bouncing on an unverifiable catch-all domain is higher when you have no prior engagement history to buffer against.
How does BounceBlock flag spam traps in a purchased or scraped cold list?
It cross-checks addresses against known spam trap patterns and high-risk domain signatures, returning a risk classification so you can remove the most dangerous entries before they reach your ESP.
Stop wasting hours on dead leads.
Upload your list and see how clean it really is — free, in under two minutes.