List Validation

Scan and validate your mailing lists to ensure ongoing delivery

Scan and validate your mailing lists to ensure ongoing delivery

Stop wasting money on bad addresses and reputation damage to boot. List validation allows you to pre-check your lists and strip out invalid or questionable email addresses, minimizing risk to your reputation.

Don’t take SMTP responses at their word; get Verified Valid™, a higher degree of certainty informed by industry best practices and decades of experience at mailbox providers and ESPs.


Get sending suggestions based on your risk tolerance

Send to more. While others may not have the data to determine real risk, 250ok’s Verified Valid™ doesn’t only find more deliverable addresses, but more addresses demonstrating recent engagement activity signals.


Enjoy a higher degree of certainty

In early benchmarks performed against market leaders (June 2019, 1M+ addresses sampled), 250ok discovered:

  • In scanning "Unknown" (unmatchable) addresses, up to 75% were determined to be deliverable
  • 99.5% of the addresses one vendor identified as “high risk” were actually Verified Vaild™
  • On compliance checks, 250ok was up to 40% better at identifying undeliverable addresses than leading validation providers

“Unlike other validation tools, I don't have to worry about paying for addresses I've already checked.”

Steven Mastrocola
Director of CRM - SeatGeek

Platform Pricing

When you get the 250ok platform, you not only benefit from market-leading email analytics, you benefit from consolidation. Consider 250ok for significant savings, because we only charge for each UNIQUE address, not total addresses.


All the bells and whistles, and then some

Single address API? Check. Batch upload API? Check. Typo corrections? Check.

Plus, 250ok is SOC 2 Type II compliant, meaning we adhere to the highest and strictest standards of data protection, so you can rest assured we don’t play around.


It's time to get the data you need and unleash your email's potential.