One batch of bad emails can tank your Instantly.ai sending domain before your first reply ever lands. BounceZero cleans your lists so your domain reputation stays intact from day one.
100 free verifications/month - No credit card required
Instantly.ai handles the sending - but it can't save a domain that's already burning. Bounces are the fastest way to end up in spam before your warm-up finishes.
Mailbox providers watch bounce rates closely. Cross ~2% and your new sending domain gets throttled or spam-foldered - often before your first Instantly.ai sequence completes.
Around 22% of email addresses decay every year as people change jobs. That list you scraped or bought last quarter is already carrying dead weight into your campaigns.
Roughly 23% of B2B domains accept mail for any address, then bounce or silently drop it later. Basic checkers mark these "valid" - BounceZero's 3-probe test tells you the truth.
Each address runs through six verification layers with up to 99.8% accuracy in internal testing on SMTP-verifiable addresses - well above the industry benchmark of ~95%.
Live SMTP-level confirmation that the inbox actually exists - the single biggest predictor of a hard bounce in Instantly.ai.
Our triple-probe test separates genuinely deliverable addresses from catch-all domains that accept everything and bounce later.
Flags info@, sales@ and admin@ addresses that rarely reply to cold outreach and often trigger spam complaints.
Removes temporary and throwaway inboxes that inflate your list size while contributing zero pipeline.
Confirms the domain can actually receive mail before Instantly.ai wastes a send - and a reputation hit - on it.
Identifies known and suspected spam traps that can get your sending domains blocklisted in a single send.
Five minutes of verification protects weeks of domain warm-up. Here's the workflow Instantly.ai users run with BounceZero.
Pull your leads as CSV from your data source - Apollo, Clay, LinkedIn scrapes, purchased lists - or export an existing lead list from Instantly.ai itself.
Drag your CSV into the bulk verifier. Up to 1,000,000 addresses per dashboard job - a typical 10K cold email list finishes in 5-10 minutes.
Mailbox existence, 3-probe catch-all, role, disposable, MX and spam trap detection run on every address at up to 99.8% accuracy in internal testing on SMTP-verifiable addresses.
Get your list back split into deliverable, risky and invalid. Keep the deliverable segment; quarantine or drop the rest.
Upload only verified addresses to your Instantly.ai campaign. Your bounce rate stays under 0.5% and your warm-up investment stays protected.
Replacing a blacklisted sending domain means new domain costs, new inboxes and 2-3 weeks of warm-up. Verification costs a fraction of that.
Common questions from cold email teams verifying lists before Instantly.ai.
Yes - via a simple CSV workflow or our API. Export your leads, upload them to BounceZero, and import the cleaned deliverable segment back into your Instantly.ai campaign. For automated pipelines, our REST API (provider-dependent response time) can verify leads programmatically before they ever reach an Instantly.ai lead list.
Always before. Once Instantly.ai sends to an invalid address, the bounce has already damaged your sending domain's reputation - no tool can undo it. Verifying first means only deliverable addresses ever enter your campaigns, keeping bounce rates under 0.5%.
Aim to stay under 2% - mailbox providers start throttling and spam-foldering senders above that. Lists cleaned by BounceZero typically bounce at under 0.5%, giving you comfortable headroom even on freshly warmed domains.
Around 23% of B2B domains are catch-all, and basic checkers mark them all "valid". BounceZero's 3-probe catch-all detection scores how likely each one is to actually deliver. Send to high-confidence catch-alls from a secondary domain, and keep unverifiable ones out of your primary campaigns.
A 10,000-email list finishes in about 5-10 minutes through the bulk verifier, and single dashboard jobs scale up to 1,000,000 addresses. You can export from your data source, verify, and load a clean list into Instantly.ai within the same working session.
$3 per 1,000 verifications - so a 10K-lead campaign costs about $30 to clean. Every account also includes 100 free verifications per month with no credit card required, so you can test accuracy on your own list before paying anything.
up to 99.8% accuracy in internal testing on SMTP-verifiable addresses. $3 per 1,000 verifications. Results in seconds. Start with 100 free verifications - no credit card required.
Verify your list before loading it into your sending platform
Salesloft review 2026: revenue orchestration, Cadence sequences, AI coaching, Drift integration
The best cold email software in 2026 compared: Instantly.ai, Smartlead, Lemlist, Outreach
Protect shared inbox pools from dirty lists
Stop bounces before Lemlist flags your account
Apollo accuracy is 70-85% - BounceZero catches the rest
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