Ezekiel 43:13

And these are measures of the altar by cubits: The cubit is a cubit and a handbreadth, and the centre is a cubit, and a cubit the breadth; and its border on its edge round about is one span, and this is the upper part of the altar.

Exodus 27:1-8

And thou hast made the altar of shittim wood, five cubits the length, and five cubits the breadth -- the altar is square -- and three cubits its height.

2 Chronicles 4:1

And he maketh an altar of brass, twenty cubits its length, and twenty cubits its breadth, and ten cubits its height.

Ezekiel 40:5

And lo, a wall on the outside of the house all round about, and in the hand of the man a measuring-reed, six cubits by a cubit and a handbreadth, and he measureth the breadth of the building one reed, and the height one reed.

Ezekiel 41:8

And I have looked at the house, the height all round about: the foundations of the side-chambers are the fulness of the reed, six cubits by the joining.

Treasury of Scripture Knowledge

Summary

And these are the measures of the altar after the cubits: The cubit is a cubit and an hand breadth; even the bottom shall be a cubit, and the breadth a cubit, and the border thereof by the edge thereof round about shall be a span: and this shall be the higher place of the altar.

Bible References

The measures

Exodus 27:1
And thou hast made the altar of shittim wood, five cubits the length, and five cubits the breadth -- the altar is square -- and three cubits its height.
2 Chronicles 4:1
And he maketh an altar of brass, twenty cubits its length, and twenty cubits its breadth, and ten cubits its height.

The cubit

Ezekiel 40:5
And lo, a wall on the outside of the house all round about, and in the hand of the man a measuring-reed, six cubits by a cubit and a handbreadth, and he measureth the breadth of the building one reed, and the height one reed.
Ezekiel 41:8
And I have looked at the house, the height all round about: the foundations of the side-chambers are the fulness of the reed, six cubits by the joining.