Can I code ZeroBounce?

Checking whether an email address is likely valid is a well-documented pattern combining format checks and a mail-server handshake — genuinely one of the more approachable builds on this register.

VIBE SCORE 99/100

how this is worked out

Why CanICodeThis says Build it

Format validation (does this look like a real email address) is a simple, well-documented regular expression
Checking whether the domain has valid mail-server records is a standard DNS lookup
An SMTP handshake to check if the mailbox actually exists, without sending an email, is a documented, if slightly delicate, technique

Read before building

Some mail providers block or rate-limit verification handshakes, so results are probabilistic, not certain
Detecting genuinely disposable or role-based addresses (info@, admin@) at scale needs a maintained list, real ongoing curation
Bulk verification of large lists needs real queue management and rate-limiting to avoid getting your own server blocklisted

Bill of materials

The parts this build actually needs, each rated on its own — the average is the Vibe Score above.

Landing page

The build spec

Build me an email verification tool: check format validity with a regex, confirm the domain has valid mail-server DNS records, and attempt an SMTP handshake to check mailbox existence without sending an email. Flag results as valid, invalid, or unknown (since some providers block verification attempts). Rate-limit checks to avoid getting blocklisted.

What it actually costs to build

Two real costs, not just "free": the AI agent's own usage, and hosting once it's running. Both are estimated from this app's own effort rating and component list — see the assumptions on the method page.

AI agent — with a subscription (Claude Pro/Max, Cursor, etc.)	$0 marginal
AI agent — pay-per-use API, no subscription	$16–$27 one-time
Hosting, once it's running	$0/mo (free tier)
Domain name, if you want your own	~$12/yr

ZeroBounce's pricing varies — check the source link on this page to compare against your own build cost.

categorymarketing

time to codean evening

Build it

their pricevaries