Extinction/CIO Method (sleep training)

I don’t want opinions on sleep training or the cry it out method. I just want to hear experiences from parents that have used the method. How long did your little one cry? How many days of this method did it take to sleep train? Did you try other methods prior?

Thanks in advance for the insights.

Edited to add: My son is 6 months. We have tried the Ferber method (going in and calming him at intervals) and it just makes it worse. He see us but gets upset that we won’t pick him up and will scream all night if we try this method. We are planning the CIO method tonight and I was just trying to see how long it took everyone else’s kids to adapt and how long they cried.

Update: It only took 2 days with the CIO method to have a baby sleeping amazingly. He lays down without a fuss, has one bottle in the middle of the night and goes right back to sleep. Thank you to everyone who gave their experiences. I really appreciate it.