Roberta Estes has written a useful post on her blog DNAeXplained about how to download a GEDCOM from your Ancestry.com tree and then uploading it to other sites; includes uploading to FTDNA, MyHeritage and GedMatch.
This is a very good how-to if you have never done this. See the post here:
Download Your Ancestry Tree and Upload It Elsewhere for Added Benefit
The following information has not been tested by me. But, as a volunteer at the Monterey Family History Center, the question about uploading gedcom files into FamilySearch.org comes up once in a while. I never know how to answer, some of my coworkers say Yes, some say No. In a message site the other day, the subject came up and a couple of links were posted as well as some advice. I have decided to share this information here (before I forget where I saw it!)
Kitty Cooper wrote about this subject 6 years ago, and updated it last year. See here:
How to add a GEDCOM to familysearch.org
Family Search themselves wrote about this subject. Here is the real story:
Tim Janzen gave me this wise counsel on the message board:
This is probably best done by people who have ancestries that are not currently very well represented in the FS Family Tree. I think that for most people the best thing to do is to find their grandparents or great grandparents in the tree and then add the genealogical data one fact at a time. I am frequently correcting errors in the tree made by people who uploaded GEDCOMs into the tree and did so in a very sloppy manner resulting in unnecessary duplicates that “cleaners” like me have to merge and get rid of after doing some careful research about the situation.
In any case, the FS Family Tree is a wonderful tool for genetic genealogists. If FamilySearch ever starts integrating genetic data into the tree it will be even more wonderful than it currently is. I learned at RootsTech that about 16 million new people are being added to the tree each month.
”The Internet is making smart people smarter and dumb people dumber.” – Kevin Drum