When you get your DNA results back from the testing company, do you feel overwhelmed by the number of matches you have? If so, you are not alone! You will recognize some people on the list, but there will be many more you don’t. To start the process of finding out who they are and how they are related to you, it can be helpful to see which side of the family they are on. That’s one reason to use the Leeds Method.
In this Learn With Me blog post, I’ll walk you through how and why to use the Leeds Method to organize your matches. You only need a little time, patience, and a spreadsheet.
Many of the testing companies now try to figure out what side of the family your matches fall into, but they aren’t perfect or complete. Sometimes it’s good to do the work yourself so you really understand the process.
That may include knowing the reason you want to find out who your DNA matches are and how they are related to you. Perhaps you or someone close to you was adopted, and you want to find that unknown parent or grandparent. Or maybe the list is too overwhelming and you don’t know where to begin. Whatever the reason, using a sorting method like the Leeds Method can help. Let’s get started!
What Is the Leeds Method?
The Leeds Method is a color-coded system that helps you sort your DNA matches into groups based on which side of the family they come from. It was developed in 2018 by Dana Leeds, a genealogist who was working on an adoption case. She needed a way to quickly group DNA matches without building a full tree for each person.
Dana noticed that when she color-coded DNA matches who shared over 90 cM with her test subject, they started to fall into four distinct groups. Each group pointed to one of the person’s four grandparents. This gave her a head start in identifying unknown parentage and also helped sort distant matches later on.
Today, many genealogists use the Leeds Method as a first step when working with unknown family lines, brick walls, or even just trying to get better organized.
What Is It Used For?
This method is especially helpful in the following situations:
- Unknown parentage or adoption
- Finding biological grandparents or great-grandparents
- Sorting matches when you don’t know where to start
- Building out tree branches more confidently
It’s most useful if you don’t already know all four of your grandparents or if you’re helping someone with unknown parentage.
Even if you do know your family tree, it’s a great way to confirm that your matches line up the way they should. Be aware, however, that it can also reveal surprises.
What You Need to Get Started
Before you begin, here’s what you’ll need:
- Access to your DNA match list (AncestryDNA works best, but you can also use MyHeritage or any other DNA testing company)
- A spreadsheet (Excel or Google Sheets)
- A list of matches that share 90–400 cM with you. You are looking to avoid matches higher than 400 cM as you don’t want first cousins or close matches. cM is called a centimorgan and is a unit of measure of how much DNA someone shares with you.
- Patience and curiosity
Step-by-Step: How to Use the Leeds Method
Here’s how to do the Leeds Method step by step. This example uses AncestryDNA, but the concept is the same from data found on other sites.
Step 1: Make a Spreadsheet
Create a blank spreadsheet with the following column titles:
- Name – use the exact name of your DNA match
- Amount of shared DNA (in cM)
- Notes – relationship if you already know it
- Blank Titles – you will fill this in later when you discover the lines of your family tree
Step 2: Start With DNA Matches Sharing 90–400 cM
This range of shared DNA usually includes second to third cousins – close enough to be useful but not too close to overlap generations.
Look through your match list and type:
- The name of each match – column A
- How much DNA they share with you – column B
- Any notes you might already know (like a known cousin or surname) – column C
- The rest of the columns will be filled with color coding.
You don’t need to include parent/child or sibling matches. Skip anyone over 400 cM, and leave out distant matches under 90 cM for now.
Step 3: Identify Shared DNA Matches
Click on the name of the first match on your list, then click “Shared Matches.” This requires a paid Ancestry subscription. You now see all the people who match you and them.
In your spreadsheet, give a color to your first match and mark it an “X” or an *. This helps you remember who the starting point was for that color group. On my list, the first person I used shared 297 cM with me. I didn’t have anyone in the 300-400 cM range.
Now, fill in a color for each person on your shared matches list. Remember, we’re only using those matches with 90 cM – 400 cM, so you won’t include the entire list. Anyone who shows up as a shared match with your first person probably belongs in the same color group.
I’ve left off names, but you see how I’ve colored in the cells from my list:
Now, go to the first match on your list that does not have a color and give them a new one. Remember to put an X or *. Click on that person’s name, then click on Shared Matches. Repeat the same procedure…go through the list of matches that you two share and give them that second color. Don’t worry if they were also in the first group.
Here is what my spreadsheet looks like with the second color (you’ll notice two matches have both red and yellow and that’s okay):
Repeat with your other matches. You’ll start to see clusters forming. Keep doing this until each of your matches in the 90–400 cM range has been sorted into a group and has at least one color. You may find you need to assign a color to someone above the one marked with an X, and that’s fine.
Step 4: Look for Four Groups
Most people will find that their matches fall into four main groups, one for each grandparent. That’s the goal.
Sometimes you’ll see three groups, or maybe five. That’s okay! Families are messy. My match list yielded 9 groups! Extra groups might mean you have:
- Endogamy (intermarriage within a community)
- Double cousins (children of siblings marrying siblings)
- Half relationships
- An unknown branch
But if you get four distinct clusters, you’ve likely mapped out the DNA lines of all four grandparents.
Here’s what my initial groupings looked like:
After doing a lot of reading on Dana’s website (www.danaleeds.com), I was able to combine those color groups that had a lot of overlap (such as blue and purple). I discovered only one match on the list that belongs to my maternal grandmother’s side. Many more of those matches share fewer than 90 cM.
Step 5: Try to Identify the Groups
If you already know some matches, try to label each group. Maybe one group includes your mom’s cousin—that tells you that group belongs to her side of the family.
Eventually, you might be able to say:
- Blue = paternal grandfather’s side
- Green = paternal grandmother’s side
- Yellow = maternal grandfather’s side
- Red = maternal grandmother’s side
This part takes time, but it helps you build more accurate trees and find new ancestors faster.
Tips for Success
- Stick to 90–400 cM to keep things simple. Smaller matches often overlap and blur the groups.
- Use known matches as anchors if you have them. A known cousin can help you label a whole group.
- Repeat with other test kits in your family. If you have a sibling or cousin who tested, the method works for their matches too.
- Watch for overlap. A match who shares DNA with two groups might be a double cousin or a sign of pedigree collapse.
Finally
The Leeds Method is one of those tools that looks simple, but can be incredibly powerful. It helps you make sense of all the DNA data in a way your brain can process.
Whether you’re building your own tree, helping someone with unknown family, or just want to get better at using your DNA results, this method is worth trying. Dana Leeds created something we can all use, no matter how complicated our family story is.
So open up your spreadsheet and get started. Your DNA matches are already giving you clues. Now, you have a way to sort them out.
Genealogy tip: If this is the first blog post of mine you’ve read on DNA and would like to read others for beginners, click here.
DNA is a powerful tool, but it can be complicated. If you’d like to learn how to use your match list to further your genealogy research, click below to get started.
