Looking on the internet deeply has found these results:

what did you say is the most popular phrase on the web.

What did you said 110,300 results on the web	what did you say 115,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Feb 17, 2015 ... up vote 1 down vote favorite. What is the correct sentence : What did you say ? or. What did you said ? The second sentence seems correct, but�... Mar 8, 2013 ... GRand THeft AUto V2 months ago. What did you said??. Read more. Show less. Reply 1. Hide replies. Nightmare Express21 hours ago. rekt?. May 21, 2013 ... Joffrey: What did you said? WHAT.. DID YOU... SAID????. Read more. Show less. 1. TheInstantClassic12 years ago. HAM ALERT, HAM ALERT�... May 8, 2014 ... Using did already establishes the tense and makes it redundant, that's why you don't say "What did you said?" I just gave a better sounding�...	Jack, what did you say to Milton? Okay, what did you say? So, what did you say to him up there? I'm sorry... what did you say? Annalise, what did you say to Billy? Joey, what did you say that offended Tom Lowery? Sorry Judy, what did you say? Chlo�, what did you say?

What did you said

110,300 results on the web

what did you say

115,000,000 results on the web

More popular!

Feb 17, 2015 ... up vote 1 down vote favorite. What is the correct sentence : What did you say ? or. What did you said ? The second sentence seems correct, but�...
Mar 8, 2013 ... GRand THeft AUto V2 months ago. What did you said??. Read more. Show less. Reply 1. Hide replies. Nightmare Express21 hours ago. rekt?.
May 21, 2013 ... Joffrey: What did you said? WHAT.. DID YOU... SAID????. Read more. Show less. 1. TheInstantClassic12 years ago. HAM ALERT, HAM ALERT�...
May 8, 2014 ... Using did already establishes the tense and makes it redundant, that's why you don't say "What did you said?" I just gave a better sounding�...