Rahman logs 174,282 sends behind Google vs Microsoft gap
Two operators, one number and one process, both pointing at the same split in your list.
Adam Rahman has put a volume figure behind the Google versus Microsoft reply gap. Across 174,282 sends, he says Google inboxes replied at 1.75% and Microsoft inboxes at 0.42%, on the same copy and the same offers. He calls it a 4.2x gap driven entirely by the inbox, and says his team rebuilt its sending infrastructure to match where the buyers actually were.
The number comes inside a longer breakdown of a campaign for a manufacturer of custom branded cups, which Rahman says produced 4,313 qualified leads. The same post describes building the pipeline in Claude Code, running every email through a three-step verification waterfall of LeadMagic, then Prospeo, then Icypeas, and routing qualified leads from EmailBison into HubSpot via OutboundSync. The call to action was a free branded cup sample, so the prospect saw their own logo on the product before any meeting.
Christian turns it into a process
Christian is making the same point operationally rather than as a statistic. He says to pull the MX record for every address on the list before sending, which tells you which provider each prospect sits behind, then split the campaign in two and run the halves as separate sends. His reasoning is that a blended campaign hides the difference in the average and you end up splitting volume evenly out of habit.
He says his team has seen the Google half come back several times higher than the Microsoft half on the same list, copy and offer. He describes it as one enrichment column to set up.
For people sending
This is the second specific figure on this split in a week. Josh Illingworth earlier put Google to Microsoft replies at 0.3%. Rahman puts Microsoft at 0.42% against Google at 1.75%. Both are describing their own lists, their own copy and their own offers, so the ratio is not a constant you can import. Rahman's 4.2x and Illingworth's number are evidence that the gap exists and that it is large, not evidence that your gap is 4.2x.
Which is the argument for Christian's version. The MX split is cheap to run and it tells you your own number instead of somebody else's. Once the halves are separate you can see which one is landing and move volume there, rather than averaging a working segment with a dead one and concluding the campaign is mediocre.
Same copy, same offers. A 4.2x gap, driven entirely by the inbox.
It's one enrichment column to set up and it changes what EVERY number after it means.