What is a fifth cousin?

2 min readUpdated 19 October 2026

Short answerYour fifth cousin is the child of your parent’s fourth cousin: you share a set of 4th great-grandparents. It works the same both ways: you are their fifth cousin too. Full fifth cousins share about 0.049% of their DNA on average.

The family line, drawn out

Follow the highlighted line from you up to the shared ancestor and down to them.

Shared ancestoryour 4th great-grandparent3rd great-grandparentyour 3rd great-grandparent2nd great-grandparentyour 2nd great-grandparentGreat-grandparentyour great-grandparentGrandparentyour grandparentParentyour parentYoustart here4th great-aunt or unclestep 1 downFirst cousin 4 times removedstep 2 downSecond cousin 3 times removedstep 3 downThird cousin twice removedstep 4 downFourth cousin once removedstep 5 downThemyour fifth cousin
6 generations up from you, 6 down to them.

How to work it out

  1. Find the nearest ancestor you share: your 4th great-grandparent.
  2. Count the generations from each of you up to that ancestor: 6 for one, 6 for the other.
  3. Take the smaller number and subtract one: 6 − 1 = 5, so they are fifth cousins.
  4. The difference between the two numbers is how many times removed: 6 − 6 = 0 (not removed).

Cousins are only “removed” when they belong to different generations. Two people in the same generation are never removed, whatever their ages.

Their family and yours

Relationships shift by one step for each generation. Here is how the people around them relate to you:

Their childfifth cousin once removed
Their parent on the shared linefourth cousin once removed
Your child sees them as your child’sfifth cousin once removed
Your parent sees them as your parent’sfourth cousin once removed
What they call youfifth cousin

Shared DNA

On average, full fifth cousins share about 0.049% of their DNA. That figure is the expected value: it halves with every generation of separation, and real amounts vary from person to person. At this distance, a DNA test may find no shared DNA at all even when the relationship is certain. A half relationship (through only one shared ancestor instead of a couple) shares about half as much: 0.024%.

Let Family Trees name it for you

In Family Trees, open anyone’s page to see how they are related to you in plain words, or choose any two people under How are they related?. The app counts the shortest blood line through birth and adoptive parents, names step, foster and in-law relations too, and uses exactly the words on this page. It’s free for a family of up to 100 people. You can also try the relationship calculator here.

Questions

What is a fifth cousin?

Your fifth cousin is the child of your parent’s fourth cousin: you share a set of 4th great-grandparents. It works the same both ways: you are their fifth cousin too.

How much DNA do you share with a fifth cousin?

About 0.049% on average. Each generation of separation halves the expected amount, and individual results vary.

What is my fifth cousin’s child to me?

Your fifth cousin once removed.