Your Knowledge Base

Finding & Merging Duplicates

How KleioBase suggests profiles that are the same person, how to read the evidence, and how to merge or dismiss them.

Last updated June 16, 2026

As you add records, the same person often turns up in several of them. Someone might appear in a birth record and again in a census taken twenty years later. Each record creates or updates a person profile, so the same individual can end up split across two or more profiles. KleioBase automatically looks for profiles that are likely the same person and suggests merging them.

KleioBase never merges automatically. It surfaces a suggestion and shows you the evidence, and you always review and decide. The profiles being matched come from Uploading Records and from the people already in Your Knowledge Base.

Before you start

Duplicate matching runs on the Researcher plan and above. On the free Explorer plan it does not run, so you will not see duplicate suggestions until you upgrade. See Plans & Billing for what each plan includes.

Matching today works only within your own knowledge base. Matching against other users' trees (community matching) is not available yet.

Where suggestions appear

When KleioBase finds a likely duplicate, it shows up in a few places so you can act on it wherever you are:

  • On your dashboard, as a count of potential duplicates.
  • On the People page.
  • In a "Potential Duplicates" section at the top of any profile that has matches.
  • In your notifications, when a new match is found.

You can start from any of these. Open the match to see who the two profiles are and why KleioBase thinks they are the same person.

Reading the evidence

Every match comes with a confidence tier and a list of signals. The tier is a quick summary of how strong the match is. The signals let you judge for yourself.

Each match lists supporting evidence, such as a matching name, a matching birth year, a shared parent, or the same record appearing on both profiles. It also lists any contradicting signals, such as different names, a large birth-year gap, or places that are far apart. Read both sides before you decide. A high tier with one nagging contradiction is still worth a careful look, and a low tier with strong supporting evidence may still be a real match.

Confidence tiers

TierColorWhat it means
StrongGreenVery likely the same person.
PossibleAmberLikely the same person, but worth checking.
WeakGrayA marginal match. Check carefully before merging.

The tier is guidance, not a verdict. You make the final call.

How to merge two profiles

When you have decided two profiles are the same person, merging combines them into one.

  1. Open the match and click Merge. This opens a side-by-side comparison of the two profiles.
  2. Choose which profile to keep. This becomes the surviving profile.
  3. For each field, such as name, dates, places, and notes, pick which value to keep. This lets you assemble the best version of the person from both profiles.
  4. If relatives of the two people also look like duplicates, they are offered as related merges. Include the ones that are genuine duplicates and skip the ones that are not.
  5. Confirm to complete the merge.

After you confirm, you land on the surviving profile so you can review the result.

What a merge does

A merge keeps one profile and removes the duplicate. It moves the other profile's records and relationships onto the profile you kept, and it combines their notes. The result is a single, richer profile with everything attached to it.

Because the combined profile now holds more information, it gets re-checked for duplicates. A merge can therefore surface new matches that were not obvious before. This is normal. Review each new suggestion the same way.

Dismissing a suggestion

Not every suggestion is correct. Two different people can share a name and a rough time period and still be distinct individuals. When a suggestion is wrong, Dismiss it. A dismissed suggestion does not come back, so you will not have to judge the same pair again.

Dismissing is the right choice whenever the contradicting signals outweigh the supporting ones, or when you have outside knowledge that the two are not the same person.

When suggestions appear

Matching runs in the background. It starts after you do something that changes your data, specifically when you:

  • Confirm records.
  • Edit a profile's key facts, such as a name or dates.
  • Merge two profiles.

A run usually finishes within a few minutes, so suggestions show up a little after you add or change data rather than instantly. If you confirm a record and do not see a match right away, give it a moment and check back.

A large import is different. It can produce matches over a longer period as KleioBase works through all the new profiles, so expect suggestions to keep arriving for a while after a big upload.

Tips for working through duplicates

  • Start with Strong matches. They are the safest to merge and clear the list quickly.
  • For Possible and Weak matches, read the contradicting signals first. They tell you what to verify.
  • Use the field-by-field choices during a merge to keep the most complete and accurate value for each detail, not just whatever was there first.
  • When relatives are offered as related merges, only include the ones you are confident about. You can always merge the others later when they appear as their own suggestions.
  • After a big merge, expect a few fresh suggestions as the richer profile gets re-checked.

For more on building out the profiles these suggestions draw from, see Uploading Records and Your Knowledge Base. To work with your people directly, head to the People page.

Still stuck? Email [email protected] or ask the Research Companion inside the app.

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