By: Katy Rowe-Schurwanz

The Family Finder™ Matrix now lets you send matches directly from the Matches page and includes new comparison views for shared cM, segments, and relationships to help with triangulation.

Unless you’ve gone really deep down the rabbit hole of autosomal genetic genealogy, you probably haven’t heard much about the Family Finder Matrix. It hasn’t received much attention over the years, but it’s an extremely useful tool for triangulating your Family Finder™ matches (autosomal DNA relatives). And we’ve just added new functionality to help your research even more!

The Family Finder Matrix

The Matrix is a companion tool to the Chromosome Browser. The Chromosome Browser tells you if a group of matches have overlapping segments on the same chromosome, but that alone isn’t enough to confirm that the group triangulates and descends from the same common ancestor.
That’s because the Chromosome Browser can’t tell you why the segments overlap. And that’s where the Matrix comes in. The Matrix lets you see if your group of matches from the Chromosome Browser also match each other.

  • If they do match each other—hooray! That’s the first step. Next, you’ll want to find others who overlap on that same segment and determine who the common ancestor is that you all inherited it from.
  • If they don’t match each other, then they don’t triangulate, and it’s time to form a new comparison group.

Previously, the Matrix let you compare up to ten of your matches to see if they also matched each other. A match was indicated by a blue box with a white checkmark in the square corresponding to each match pair in the grid. If there wasn’t a match, the square remained blank.

To select matches for comparison, you had to scroll through an alphabetical list of all your Family Finder matches. That could be pretty tedious—especially when you have several thousand matches!

The New and Improved Family Finder Matrix

We’ve made some exciting improvements to the Family Finder Matrix to make it easier to select matches for comparison and to provide better insights into how those matches connect to each other.

Easier Ways to Select Matches

We’ve expanded the ways you can add matches to the Matrix! Now, you can select matches directly from your Family Finder Matches page.

Screenshot of the Family Finder Matches page on FamilyTreeDNA, showing DNA match details, relationship ranges, and selected matches for comparison in the Family Finder Matrix. The interface includes checkboxes for selecting matches and a pop-up menu to compare them in the Matrix or Chromosome Browser.

To select matches from the Family Finder Matches page, simply check the box next to your match’s name. Once selected, the match will be added to a list at the bottom of the page, where you’ll see options to compare them in either the Chromosome Browser or the Matrix.

  • You can select up to seven matches to compare in the Chromosome Browser.
  • You can select up to ten matches to compare in the Matrix.

All Family Finder Matches page filters, sort options, and search functions are available to help you find the matches you want to compare. When you’re ready, just click the “Compare with the Matrix” button, and the Matrix will open in a new tab.

Screenshot of the Family Finder Matrix selection interface on FamilyTreeDNA. The image displays the options for selecting up to ten DNA matches, filtering available matches, and comparing selected matches using the Chromosome Browser or Matrix.

Of course, you can still select matches for comparison from the Matrix page itself. At the top left, you’ll see a list of your matches, alphabetized by last name. Click a match’s name in that menu, then click the “Add” button to the right.

To remove a match from the comparison, select their name from the list at the top right, then click “Remove.”

Three New Ways to Compare Matches

There are now three ways to view the results of your comparison in the Matrix:

  1. Total Shared cM: View how many shared centiMorgans (cM) each match has with each other.
  2. Number of Shared Segments: See how many DNA segments each match shares with each other.
  3. Predicted Relationship Range: View the predicted relationship range between each match.

Total Shared cM

The Total Shared cM view is the default setting. It displays the number of centiMorgans (cM) that each match shares with another match. Just like on the Matches page, this will not include shared cM on the X chromosome.

Screenshot of the Family Finder Matrix displaying the Total Shared cM view, showing the number of centiMorgans (cM) each match shares with another. The table lists multiple DNA matches and their shared cM values, excluding X chromosome data.

The number of shared centiMorgans can help you determine the actual relationships between your matches. While FamilyTreeDNA provides a predicted range for each relationship, third-party tools like DNA Painter can help refine those estimates even further.

Number of Shared Segments

The Number of Shared Segments view shows how many overlapping DNA segments each match shares with another match. This also does not include segments on the X chromosome.

Screenshot of the Family Finder Matrix displaying the Number of Shared Segments view. The table lists DNA matches and the number of overlapping segments they share, excluding segments on the X chromosome.

Why is this useful?

  • If two matches only share one segment, that segment is likely the same one they both overlap with you on—bingo! That’s triangulation!
  • If they share multiple segments, they could be close relatives. This means they may not be ideal candidates for your triangulation group.
  • They might share two different common ancestors with you and another with each other.
  • Or, they could all share the same common ancestor with you and each other.
  • More investigation will be needed to confirm the exact connection.

Predicted Relationship Range

The Predicted Relationship Range view displays the estimated relationship range between each match.

Screenshot of the Family Finder Matrix displaying the Predicted Relationship Range view. The table shows estimated relationship ranges between DNA matches, such as 2nd to 4th cousins or 3rd to 5th cousins, helping users determine likely genealogical connections.

The predicted relationship range is helpful because you don’t want to use matches that are closely related to each other, like parents and children or siblings. If two of your three matches are predicted to be parent and child, that increases the chance that the third match is identical by chance rather than by descent.

How to Use the Family Finder Matrix With Other Autosomal Tools

The Family Finder Matrix is a companion tool to both the Chromosome Browser and the Family Matching tool—but how do you use all three together to analyze your DNA matches effectively?

Each tool provides a different piece of the puzzle when identifying whether a group of matches shares a common ancestor or if some matches are coincidental. Understanding how to combine these tools will help you determine whether your DNA matches are from your maternal side, your paternal side, or both—or if some matches are Identical by Chance (IBC).

Let’s break it down step by step.

The Chromosome Browser: Identifying Overlapping DNA Segments

Screenshot of the FamilyTreeDNA Chromosome Browser displaying shared DNA segments with multiple matches. The image shows a chromosome view highlighting overlapping segments in different colors, representing shared DNA regions with selected matches.

The Chromosome Browser allows you to view and compare the DNA segments you share with your Family Finder matches.

Everyone has two copies of chromosomes 1–22, but the Chromosome Browser does not distinguish whether overlapping segments come from the same ancestor or from two different ancestors.

When a group of matches shares an overlapping segment in the Chromosome Browser, there are a few possible explanations:

  1. They all share the same common ancestor on your maternal side.
  2. They all share the same common ancestor on your paternal side.
  3. Some share a common ancestor on your maternal side and others on your paternal side—meaning they represent two different ancestors!
  4. One or more of the matches is Identical by Chance.

So, how do you figure out which of these possibilities is correct? That’s where the Family Matching tool comes in.

Parental Phasing: Sorting Matches by Maternal and Paternal Sides With The Family Matching Tool

The Family Matching tool helps determine whether a match belongs to category 1, 2, or 3 from the list above.
This tool sorts your Family Finder matches into three buckets based on which side of your family they match:

    • Paternal side
    • Maternal side
    • Both sides (for matches who are related to you on both your paternal and maternal lines)

To use the Family Matching tool, you need to link matches to your family tree. When you know a match’s connection, add their lineage to your tree and link them to their correct spot.

Once a match is linked, the tool analyzes their overlapping DNA segments with you and compares them to all your other matches. It then places them into the appropriate maternal or paternal bucket, depending on how you linked them.

Some key things to remember:

        • You must link at least one paternal-side match to create a paternal bucket.
        • You must link at least one maternal-side match to create a maternal bucket.
        • You must link both a paternal and a maternal match to create a bucket for matches on both sides.

The closer the linked match is, the more matches will be sorted into buckets. Linking a parent will bucket most of your match list, while linking a fourth cousin won’t bucket as many matches.

How does Family Matching help?

The Family Matching tool helps clarify which side of your family a group of matches belongs to:

        • If all your matches are in the maternal bucket, they share a common ancestor on your mother’s side.
        • If all your matches are in the paternal bucket, they share a common ancestor on your father’s side.
        • If your match group is a mix of maternal and paternal matches, they represent at least two different common ancestors.

Even if all matches are sorted into one bucket, that doesn’t necessarily mean they all descend from the same common ancestor. You’ll still need to do more triangulation to confirm the connection.

Identical by Chance: When Matches Aren’t Actually Related

Not every DNA match is a true relative—some are Identical by Chance (IBC) rather than Identical by Descent (IBD).
Identical by Descent:

        • The match shares DNA with at least one of your parents.
        • You and the match descend from a recent common ancestor.

Identical by Chance:

        • The match does not share DNA with either of your parents.
        • There is no recent common ancestor, despite sharing DNA.

So why do IBC matches even appear?

When DNA is passed down from your parents, it’s randomly recombined—like shuffling a deck of cards before dealing. The matching algorithm doesn’t distinguish which segments came from your mother and which came from your father. It simply looks for other testers who share segments of DNA with you.

To reduce the likelihood of IBC matches, minimum segment size thresholds are built into the matching algorithm. However, some false matches will still appear—especially distant matches.

How to Identify IBC Matches

The easiest way to identify IBC matches is by testing both of your parents:

  • If a match also appears in at least one parent’s match list, they are IBD.
  • If a match does not appear in either parent’s match list, they are likely IBC.

If you can’t test your parents, you can still filter out IBC matches using triangulation in the Chromosome Browser and the Matrix.

Confirming Triangulation With The New Family Finder Matrix

Triangulation is the process of confirming that a group of matches all share the same DNA segment inherited from a single common ancestor. The Chromosome Browser and Matrix are powerful tools, but they have limitations—you’ll need to take additional steps to confirm that your matches not only share DNA with you but also with each other on the same segment.

Here’s how to do it.

Step 1: Do Your Matches Share the Same Segment with Each Other?

One limitation of both the Chromosome Browser and the Matrix is that they can’t tell you whether your matches also share DNA with each other on the same segment.

If your matches only share one segment with each other, that segment is likely the same one they share with you.

If they share more than one segment, it’s unclear whether the segment they share with you is also the one they share with each other.

So how do you figure it out?

In this scenario, you’ll need to reach out to your matches and ask them to compare each other in their Chromosome Browser to see if they also overlap on the same segment.

  • If they do, great! You’ve confirmed triangulation.
  • If they don’t, then they likely share a different common ancestor with each other than they do with you.

Step 2: Identifying the Shared Common Ancestor

Once you have a group of matches who all overlap on the same segment with you and with each other, the next step is figuring out who passed that DNA segment down.

Analyzing Family Trees

To do this, you’ll need to examine each match’s family tree and look for shared patterns:

    • Do they have common surnames?
    • Do they have ancestors from the same location?
    • Do any of their family lines overlap in historical records?

Of course, not all family trees are perfect. Some may contain errors or incorrect assumptions, so you’ll need to carefully evaluate sources or do your own research if their trees lack documentation.

Using Shared Matches to Narrow Down Possibilities

You may not be able to identify the common ancestor for every triangulated group—and that’s okay! But as you confirm ancestors for other groups, look for shared matches between those groups and your unknown groups.

If a known ancestor group shares a significant number of matches with an unknown group, you may be able to narrow down potential ancestors.

Using Y-DNA and mtDNA to Strengthen a Hypothesis

If multiple members of your unknown group are direct paternal or direct maternal descendants of a suspected ancestor, Y-DNA and mtDNA testing can help confirm the connection.

If they match each other through Y-DNA or mtDNA, it strongly suggests that your hypothesis is correct.

This can also help you identify additional matches who share DNA with the same ancestor—even if you missed them in your original triangulation analysis.

Addressing Endogamy and Pedigree Collapse

Some genealogical situations make triangulation more difficult—especially if you have ancestors from an endogamous population or experience pedigree collapse.

What Is Endogamy and Pedigree Collapse?

Endogamy occurs when people within a genetically isolated population (due to cultural, religious, or geographical isolation) repeatedly marry within the same group over generations.

Pedigree collapse happens when cousins marry cousins, meaning you descend from the same ancestor multiple times.

These factors increase the amount of shared DNA between distant relatives, making it harder to determine a true genealogical relationship.

How Endogamy Affects Triangulation

You’ll likely have more autosomal matches who share more DNA than expected for their predicted relationship.

You’ll encounter more IBC matches, as there is more overlapping DNA within the population.

To improve accuracy, focus on larger overlapping segments—ideally 20 cM or greater—when attempting to confirm triangulation in endogamous or pedigree collapse situations.

Explore More: Resources for Understanding the Family Finder Matrix and Triangulation

If you want to better understand how to use the Family Finder Matrix, Chromosome Browser, Family Matching, and triangulation, there are great resources available to help you make the most of your DNA results.

FamilyTreeDNA Help Center: Mastering the Tools

The FamilyTreeDNA Help Center offers step-by-step guides on key tools, including:

Roberta Estes’ DNA-Explained Blog & Book: Advanced Strategies
For detailed guides, triangulation strategies, and case studies, check out:

The more you learn, the better equipped you’ll be to unlock the full potential of your DNA results!

Headshot of Katy Rowe-Schurwanz - Product Manager at FamilyTreeDNA

About the Author

Katy Rowe-Schurwanz

Product Manager at FamilyTreeDNA

Katy Rowe-Schurwanz has always been interested in genealogy, inspired by her maternal grandparents, who told her stories about their family and family history when she was little. After studying anthropology and history in college, she joined FamilyTreeDNA in 2015 and became the Trainer for Customer Support. Katy created and improved training processes and was fundamental in the creation of the Big Y Specialist team. In September 2021, she became Product Manager and has focused closely on improving FamilyTreeDNA’s genetic genealogy products.