Email validators

Before launching any email campaign, it is important to make sure that your infrastructure is configured correctly: DNS records, IP reputation, validity of recipient addresses. One incorrectly written SPF can send the entire campaign to spam, and an address from an old database can increase the bounce rate and undermine the reputation of the domain.

Bulko собирает четыре базовых проверки в одном месте — все работают прямо в браузере без регистрации, по нашим внутренним инструментам, которые мы используем сами для своих рассылок.

Email Validator

Checks an email at three levels: syntax (format correctness), the domain's MX records (whether a mail server exists), and server availability (whether SMTP responds). Use it before importing a large list — it helps filter out non-existent addresses that would otherwise turn into bounces.

MX Checker

Shows the domain's MX servers with priorities. Useful for diagnostics: if MX records are missing or misconfigured, emails will not be delivered. It also helps identify which mail provider the recipient uses — Gmail domains have MX pointing to gmail-smtp-in.l.google.com, Outlook to mail.protection.outlook.com.

SPF Checker

Analyzes the domain's SPF record. SPF is a TXT record in DNS that lists the servers allowed to send mail on behalf of your domain. Without a correct SPF, many providers (especially Gmail) add a "Sent via" label or send the email straight to spam. The checker will show syntax errors and critical permissions like +all that break the protection.

Blacklist Checker

Checks the domain and IP address against 50+ public DNS-RBLs: Spamhaus, Barracuda, SORBS, SpamCop, and others. If your SMTP is on a blacklist, providers discard emails before even looking at the content. Run the check regularly: blacklisting often happens after mass mailings with suspicious activity.

When to run checks

• Before the first campaign from a new domain — check SPF and MX.
• Every 1-2 weeks for active domains — to monitor blacklists.
• After importing a new list — run it through the email validator to filter out invalid addresses.
• After any DNS changes — make sure SPF isn't broken.

Все валидаторы интегрированы в платформу. В дашборде Bulko они доступны прямо из интерфейса кампании — ничего отдельно копировать не нужно.