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Triangle Centroid

The centroid is simply the average of the three coordinates. It is where the medians meet, and a paper triangle balances on it. The area comes from the shoelace formula.

Your numbers

Centroid x

3.667

Centroid y

3

Area

25

Formula

Centroid x = (x₁ + x₂ + x₃) ÷ 3

The centroid cuts each median in a 2:1 ratio — two parts towards the vertex, one towards the opposite side.

What to enter

InputDefaultAccepted range
x₁The horizontal coordinate of the first point.0No limit
y₁The vertical coordinate of the first point.0No limit
x₂The horizontal coordinate of the second point.8No limit
y₂The vertical coordinate of the second point.2No limit
x₃The horizontal coordinate of the third point.3No limit
y₃The vertical coordinate of the third point.7No limit

Step by step

FormulaCentroid x = (x₁ + x₂ + x₃) ÷ 3
With the default numbersCentroid x = (0 + 8 + 3) ÷ 3
AnswerCentroid x = 3.667

Quick reference table

Results when only x₂ changes and everything else stays put.

x₂Centroid xCentroid yArea
42.333311
63318
83.667325
125339
166.333353

What each result means

ResultAt default values
Centroid xThe average of the three x values — the centroid’s x.3.667
Centroid yThe average of the three y values — the centroid’s y.3
AreaThe space a shape covers — length squared.25

Common mistakes

The centroid cuts each median in a 2:1 ratio — two parts towards the vertex, one towards the opposite side.

Glossary

x₁
The horizontal coordinate of the first point.
y₁
The vertical coordinate of the first point.
x₂
The horizontal coordinate of the second point.
y₂
The vertical coordinate of the second point.
x₃
The horizontal coordinate of the third point.
y₃
The vertical coordinate of the third point.
Centroid x
The average of the three x values — the centroid’s x.
Centroid y
The average of the three y values — the centroid’s y.
Area
The space a shape covers — length squared.

Frequently asked questions

Q. How is Triangle Centroid calculated?

Centroid x = (x₁ + x₂ + x₃) ÷ 3 — The centroid is simply the average of the three coordinates. It is where the medians meet, and a paper triangle balances on it. The area comes from the shoelace formula.

Q. Can you walk through an example?

With x₁ 0, y₁ 0, x₂ 8, y₂ 2, x₃ 3, y₃ 7, the answer is Centroid x 3.667.

Q. What do I need to enter?

Enter x₁, y₁, x₂, y₂, x₃, y₃. The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only x₂ moves the answer to x₂ 4 → Centroid x 2.333 and x₂ 16 → Centroid x 6.333. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

The centroid cuts each median in a 2:1 ratio — two parts towards the vertex, one towards the opposite side.

Related calculators

Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.