Open your DNA match list on any testing site and you are staring at hundreds, sometimes thousands, of names attached to percentages and centimorgan numbers that mean very little on their own.
Some of these people are second cousins. Some are fourth cousins twice removed. Almost none of them come with an explanation of how they actually fit into your family tree.
The Leeds Method fixes that without needing anyone to already know the answer.
Developed by genealogist Dana Leeds in 2018, it uses a simple color coding system to sort your matches into four groups, one for each of your four grandparents, using nothing more than a spreadsheet and the shared match feature every major DNA testing site already gives you.
This guide walks through the entire process, from picking which matches to include to building the grid one person at a time, along with the mistakes that can throw the whole thing off.
What the Leeds Method Actually Does
Everyone has four grandparents, and roughly speaking, each DNA match you have connects to you through one of those four family lines. The problem is that a match list on its own does not tell you which line a person belongs to.
The Leeds Method solves this by using a feature almost every DNA testing company offers called shared matches, sometimes labeled as in common with. This feature shows you which of your other matches also match a specific person.
If two of your matches share DNA with each other and with you, there is a good chance they connect to you through the same grandparent. The Leeds Method uses that overlap to sort your entire match list into four color coded groups, one per grandparent, before you even know which specific ancestor connects any of them to you.
What You Need Before You Start
You will need a DNA test result from a company with a shared match tool, such as AncestryDNA, MyHeritage, FamilyTreeDNA, or 23andMe. You will also need a spreadsheet program, whether that is Google Sheets, Excel, or something similar.
Beyond that, the only real requirement is patience, since building the grid means clicking through each match's shared match list one at a time.
Choosing the Right Range of Matches
Not every match on your list is useful for this method. Matches closer than a first cousin, such as parents, siblings, or children, share too much DNA with you to sort cleanly into one grandparent's line, since they are connected through multiple lines at once. Leave those off the grid entirely.
On the other end, matches below roughly 20 centimorgans get unreliable fast, since a small shared segment is more likely to be a coincidental overlap rather than a real, traceable relationship. Most people building a Leeds Method grid work with matches roughly between 20 and 400 centimorgans, which usually lands somewhere in the second cousin to fourth cousin range.
Setting Up Your Spreadsheet
Start a new spreadsheet and list your matches in the first column, sorted from your closest match down to your most distant, using the cutoff range from the previous section. Include their shared centimorgan amount next to their name so you can keep track of where each person falls.
Leave the rest of the columns empty for now. You will fill those in as you work through the shared match comparisons in the next step.
Building the Four Color Groups Step by Step
Starting With Your Closest Match
Take the match at the very top of your list, meaning your closest match within the range you chose. Assign this person a color, say yellow, and fill in their cell.
This person becomes the seed for your first group. Every other match who shares DNA with this person, according to the shared match tool, will likely get the same color.
Checking Shared Matches for Each New Person
Move to the next match on your list and open their shared match list on your testing site. Look through it for names that already appear on your spreadsheet.
If this new match shares DNA with your first yellow match, give them the same yellow color in the next available column on their row. Keep working down your list this way, checking each match's shared matches against the names you have already colored.
When to Start a New Color
Eventually you will reach a match whose shared match list does not overlap with your existing yellow group at all. This person likely connects to you through a different grandparent, so give them a new color, such as blue, and start a second group.
Continue down your list the same way. Most people end up with exactly four colors by the time they reach the bottom, since there are exactly four grandparents to sort into.
What to Do When Someone Fits Two Groups
Every so often, a match will show overlap with two different color groups at once. This usually means two of your family lines intersect at some point further back, a situation genealogists call endogamy, which is especially common in certain ethnic and regional populations.
When this happens, mark the match with both colors rather than forcing them into one. It is useful information about your family tree, not a mistake in your spreadsheet.
Making Sense of the Colors Once You Are Done
A finished grid gives you four color groups, but it does not automatically tell you which color belongs to which grandparent. To figure that out, look for any match in each group whose connection to you is already known, whether that is a second cousin you recognize by name or a match who has a family tree attached that overlaps with yours.
Once you identify even one confirmed relative in a color group, you can label the entire group with that side of the family. From there, unfamiliar surnames inside that same color group become new leads worth researching, since they almost certainly connect to you through that same grandparent.
Common Mistakes That Throw Off the Whole Grid
The most common mistake is including matches that are too close, like a full sibling or a parent, which muddies the grid since they connect to more than one grandparent line at once.
Another common mistake is including too many distant, low centimorgan matches, which introduces false positives that do not represent a real genealogical connection. It is better to have a smaller, more reliable grid than a large one full of noise.
Endogamy is the other big variable. If your family comes from a small or historically close knit community, you may find far more overlap between colors than the standard four groups would predict, and the method still works, but it takes more patience to interpret.
Taking It Further, Splitting Each Color Into Two
Once you have four solid color groups, you can apply the same method again inside a single group to split it further. Since each grandparent had two parents of their own, running the Leeds Method a second time using only the matches inside one color can often divide that group into your great grandparents' two family lines.
This second pass works exactly the same way as the first, just with a smaller starting list.
Why This Kind of Puzzle Matters Beyond the Spreadsheet
It is easy to treat a DNA match list as a numbers game, a pile of percentages waiting to be sorted. But every name on that grid is a real person connected to you through a real ancestor who lived an actual life, most of which never got written down anywhere.
The Leeds Method will not tell you what that ancestor was afraid of as a kid, or the year they fell in love, or the joke they told at every family dinner. It will just tell you which line to start looking down. The stories still have to come from somewhere, usually from the family members who are still around to tell them, while there is still time to ask.
That is really the other half of family history work. Sorting matches into the right lines tells you who you are related to. Getting someone in that line to actually record their memories is what keeps the story attached to the name.
Memoracy was built for exactly that part, giving family members a simple daily prompt to write down their own life in their own words, so the names on a chart like this one come with an actual voice behind them.
Sign up and start your first story on Memoracy today.
