What is Seedlist Weighting and Why is it Important?

Seedlist weighting is the ability to assign specific percentages, or “weighting,” to each individual ISP in Inbox to make your seed results more accurately reflective of where you send mail. If you’re not sure where you send mail, you can leverage our Seedlist Optimizer to determine how your list should be weighted.

By weighting your seedlist, Inbox can give you a more accurate reflection of your deliverability and inbox placement based on where your mail is actually going. While most deliverability tools have traditionally treated all receiving mailboxes (ISPs) as equals, 250ok tailors your seed testing around your mail stream.

In turn, you take the guesswork out of which ISPs are priority and where to focus your resources. For instance, if you’re showing 100% missing mail at AT&T but it makes up less than 1% of your list, it’s not the optimal use of your time to diagnose the problem. Weighting your seedlist helps you filter out the noise and focus on what’s important.

  • NOTE: If you choose to leave the “Include zero weight items in seedlist” box unchecked and apply the optimized weighting, anything with zero weight is excluded from the seed list when exported.

EXAMPLE: Seedlist weighting will remove the seed results from your view that are not part of your mailing list.  If your list is mainly B2C and US based, your results will not display the European and Asian mailbox providers that you are not mailing to.



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