Over 1 million people in their database as of 30 January 2018, with only 20% being transfers.
DNA Matches – Both reports will be e-mailed to you
Export entire DNA Matches list
Export shared DNA segment info for DNA Matches
File contains:
  1. match name
  2. chromosome number
  3. start & end points 
  4. RSID (aka SNP) start & end points 
  5. cM size of the match
  6. number of SNPs tested
Chromosome Browser:
Identifies some portions not tested:
2018 Salt Lake Christmas Tour Presentation and Speech
2019 Statistics (per MyH's 12/30/2019 Blog, MyHeritage News)
10 year history numbers:
69 million users
3.07 billion family tree profiles
acquired 7 companies
welcomed 406 employees
2019 numbers:
131 new employees
1.5 billion historical records added
3.77 million DNA database testers
36 new health reports
757 million new family tree profiles
69 new webinars
presenting partner of Eurovision 2019
845 new knowledge base content items.
MyHeritage began selling autosomal test kits in 2016.  They ran a European ad campaign and purchased Promethease in 2019.  Their database size was 3.7 million as of 31 Dec 2019.1
Update to Theory of Family Relativity™ 7 May 20202
The Theory of Family Relativity™ leverages all the data available on MyHeritage, such as family trees and historical records, to provide you with plausible theories as to how you may be related to a given DNA Match. We run updates and refresh the data periodically, and we’ve just refreshed the data again this week.
MyHeritage’s databases have grown considerably since the last update, including millions more family trees and over 2 billion additional historical records (bringing us to a total of over 12 billion records). That means that there’s an excellent chance those of you who have been stumped or stuck on certain DNA Matches may receive answers and new insights about your ancestors and family relationships.
Theory of Family Relativity™ update by the numbers:
The total number of theories has increased from 14,260,864 to 20,330,031 — a 42.6% increase.
The number of DNA Matches that include a theory increased by 42.5% from 9,964,321 to 14,201,731.
Sometimes we arrive at a theory through multiple paths, indicating a strong theory and providing additional supporting evidence. After the previous update, there were a total of 115,106,944 paths. This update increased the number of paths by 40.5% to 161,762,761.
The number of MyHeritage users who now have at least one Theory of Family Relativity™ for their DNA Matches has increased by 33.6%.
How to find out if you have new theories:
 If we have found new theories for you in this update, you’ll see a banner about the Theory of Family Relativity™ at the top of your DNA Matches page. Click “View theories” to see all the theories we’ve found, both old and new.
This banner, indicating that you have new theories, will be available for a few weeks, after which you can access your theories by going to your DNA Matches page. 
Whenever a DNA Match has a theory, this will be indicated in the DNA Match card. You can also filter your DNA Matches to see only those with a Theory of Family Relativity™ by clicking on the Filters icon. In the first group of filters, select “Has Theory of Family Relativity™.” 
You will also see a “NEW” badge next to new theories that were just added. This indication will appear for 30 days. 
Theory of Family Relativity™ is a premium feature that requires a site subscription on MyHeritage (Premium, PremiumPlus, or Complete). Users without a subscription will still see all the theories that we found for them, but when they click on the theory to view the full details, some of the information will be hidden. Users who upload their raw DNA data from another testing service to MyHeritage and do not wish to purchase a subscription can pay a one-time fee of $29 per kit to unlock all advanced DNA features offered by MyHeritage, including Theory of Family Relativity™. 

Complete subscription

Explore 12.2 billion international historical records, and receive automatic matches between individuals in your tree and millions of other trees. You can instantly search billions of records. 

Join over 100 million users who have already built family trees totaling 3 billion tree profiles.

The Complete plan gives you full access to all MyHeritage advanced features, including:

 Unlimited family tree size (option to upload a GEDCOM file)

 12.2 billion international historical records

 Unlimited colorization of black and white photos with MyHeritage In Color™

 Automatic Smart Matches™ with millions of family trees

 Automatic Record Matches

 Instant Discoveries™, which can add an entire branch to your family tree with 1 click

 Consistency Checker, which automatically identifies inaccuracies in your tree

 Advanced DNA features


 Family Tree Builder software premium edition

 Priority customer support via phone and email 24/7

1 See "2019: The Year and Decade of Change," DNAeXplained - Genetic Genealogy blog, dated 31 Dec 2019.
2 See "Update to Theory of Family Relativity," MyHeritage Blog, dated 7 May 2020.