Genealogy compare

The Genealogy compare tool compares genealogies to find common individuals using geographical areas with similar cities and lastnames, and similar events.

It can both compare genealogies that you have locally on your computer and genealogies held by other Ancestris users. For this, you do no need to share any sensitive information to anybody.

To compare genealogies with other Ancestris users, you simply need to let Ancestris share basic information such as lastnames, time ranges and location areas. Your genealogy is never transferred to a server or to anybody and private information can remain confidential.  If a match is found, you can contact the corresponding Ancestris user by email.


An Ancestris innovation

The idea behind this innovation is to leverage the data of the Ancestris user community without having to give the data away nor to upload it on a server.

The objective of this tool is to find connections between genealogies, which will then help you develop your own genealogy.

This tool is easy to use and gives you in just a few mouse clicks a quick overview showing whether two genealogies have anything in common.

A genealogy can be compared with several other genealogies at the same time.

These other genealogies can be made of local Gedcom files open in your Ancestris application, or they can be genealogies of other users using Ancestris at the same time as you.

When comparing genealogies across different users, your data remains protected and you keep control of your data. This is a key principle of the Ancestris community we are part of.

You can compare genealogies and find connections between you and other users' genealogies in two ways:

Either you find them or they find you. Either way, you will benefit.

Once users have found possible common ancestors, they can contact each other to find out more. They are free to establish the contact or not. 

Common ancestors are only possible if they both share an event in the same space-time !

Area-period, a "space-time" concept

In order to easily compare genealogies, we have defined area-periods.

We have divided the physical world space into areas. These areas follow the definition of the Geonames database. An area is approximately a county in the US, a district in England or a department in France. In this tool, an area is made of 3 elements separated by a dot : the country, the first level of Geonames jurisdiction, and the second level.

We have divided the time dimension into periods. We have defined periods of 10 years to match with the decennial tables that may exist in the official genealogical repositories.

Each located and dated event of a genealogy can therefore be located in an area-period. An area-period can include several events.

As a result, two genealogies have something in common if at least an event of each genealogy took place in the same area-period.

Data Privacy

When comparing genealogies across different users, information sharing is carried out in complete confidentiality and following a deliberate choice from you to "share" some basic information about your genealogy.

The basic information shared is the "flash list report of events" of your genealogy. It is made of city names, lastnames, and dates of events. None of this information is sent to a server. It is merely exchanged through temporary messages.

In other words, only common data can be seen by each user.

Users do not have access to your computer. The data exchange works like a phone call. Your Ancestris application chats with the other person's Ancestris application and only when common information is detected can you see the corresponding overlaps and events if they exist.


There are 3 pre-requisites to use all possibilities of this tool.

In order to compare genealogies, you must locate and date as many events as possible, and  you must specify the locations of your genealogy using the places editor. If you did not use this editor to structure your places descriptions, Ancestris will try to find these places directly in the geonames database and make the best of it.
Dates can be approximated or use date ranges.
Events that are neither dated nor located cannot be compared for obvious reasons.

In order to compare genealogies with other users, you must fill in your user profile with a user-name, a picture and an valid email.

The communications occurs on port 5448. Be sure that this port is open in your firewall configuration.


The Genealogy compare tool handles local genealogies and 'connected' genealogies.

Local genealogies are Gedcom files that you have on your computer.

Connected genealogies are the Gedcom files held by other Ancestris users who have decided to share their genealogy for comparison.

The tool compares one main local genealogy with all the other ones, local or connected.

You decide which one of the local genealogies will be the main genealogy to compare with all others.

Only the main genealogy of each user can be shared at a given time with the other users.

Each genealogy is represented by a little window and placed into the display area of the workspace, the comparison area.

The rest of the tool is made of a window title and a toolbar.

The comparison area

The central part of the window shows 3 types of windows :

Local Genealogies

Each open genealogy in Ancestris appears and is represented by a little window.

These windows look like this:

en-compare-local-main.png en-compare-local-other.png
The main local genealogy
in blue with 2 buttons

The other local genealogies

in green with 1 button

Meaning of icons and check boxes

The title of this window is the name of the genealogy.

An icon is displayed at the left hand side of the window title:

In the window are displayed four numbers:

Two check boxes on the right hand side have the following purpose :

Context menu of a local genealogy

A right-click on the window displays a context menu:


Your profile

When you display you profile you should see the following window:


Your profile displays the information you specified in the preferences of the Genealogy compare tool. See the corresponding section below.

In addition, it displays the number of connections you made to other users and the period of time during which you made them.

Connected genealogies

The main local genealogy of another Ancestris user becomes a connected genealogy for you once they have decided to share it for comparison.

A connected genealogy can be active or inactive.

It is active when the user is currently sharing its main genealogy. It becomes inactive when the user is no longer sharing it.

Connected genealogies look like this:

en-compare-remote-active.png en-compare-remote-inactive.png

Active connected genealogy

in red.
Comparing is possible.

Inactive connected genealogy

in grey.
Comparing is no longer possible.

Meaning of icons and check boxes

The title of this window is the name of the user.

A icon is displayed at the left hand side of the window title:

In the window are displayed four numbers:

Two check boxes on the right hand side have the following purpose :

Context menu of a connected genealogy

A right-click on the window displays a context menu:


User profile

When you display a user profile you should see the following window:


A user profile displays the information specified in the preferences of the Genealogy compare tool for the other user.

In addition, it displays the number of connections they made to you and the period of time during which they made them.

Also, an email button email.png helps you contact the user by opening up your client mail and preparing a mail to their attention.


For each comparison between the main genealogy and another one, local or connected, a comparison window is shown.


Meaning of icons and buttons

The title of this window is 'Comparison' and an double compared tree comparegedcom.png appears at the left hand side of the window title.

The first element in the window is the overlap between the two compared genealogies. The percentage indicates the ratio of common area-periods over the total number of area-periods.

In the window are displayed two numbers:

Two buttons are available on the right hand side of the window:

Comparison map

The Comparison map is the following window:


This window displays your genealogy in blue circles and the compared genealogy, local or connected, in green circles.

Each circle represent an area-period. See definition above. The larger the circle, the more ancient the period is.

Common area-periods are displayed in red. Here we can see 18 area-periods in common between your genealogy and the Kennedy genealogy located at Los Angeles, Phoenix, Chicago and New York. Several periods can exist for a given location.

For a comparison map with a connected genealogy, only the common areas of the connected user are displayed. In the example below, we only see 12 area-periods of Steven's main genealogy, called 'Collins'. These are areas in Boston and Vermont.

As you can also see, the blue circles are the same as they represent the same area-periods of the my genealogy, the 'Harper' genealogy.