Biblical Unit Converter
Cubits ↔ Feet
Shekels ↔ Grams
Ephahs ↔ Liters
Working values: 1 common cubit = 18 inches (45.72 cm); 1 shekel = 11.4 grams; 1 ephah = about 22 liters. Ancient measures were not perfectly uniform, so treat every result as an approximation. Estimates for the ephah in particular vary between scholars.
The Cubit
The cubit was the standard measure of length in the Hebrew Scriptures: the length of a man's forearm, from the elbow to the tip of the middle finger. The common cubit is usually reckoned at about 18 inches (45 cm). A longer “royal” cubit of about 20.6 inches (52.4 cm) is known from surviving Egyptian measuring rods.
Scripture itself shows that more than one cubit was in use. Og's bed was measured “by the cubit of a man,” Solomon's house by “the former measure,” and Ezekiel's measuring reed by a cubit with a span added:
For only Og the king of Bashan remained of the rest of the giants. Behold, his bedstead was a bedstead of iron; [is] it not in Rabbath of the sons of Ammon, nine cubits long and four cubits broad, by the cubit of a man?
Deuteronomy 3:11 (KJ3)
And these [were] founded [by] Solomon, to build the house of God: the length by cubits [according to] the former measure, sixty cubits; and the breadth twenty cubits.
2 Chronicles 3:3 (KJ3)
And, behold, a wall on the outside of the house round about. And a measuring reed was in the man's hand, six cubits, with a cubit and a span. And he measured the breadth of the building, one reed; and the height, one reed.
Ezekiel 40:5 (KJ3)
The Hebrew word: אַמָּה (ammah)
The word translated “cubit” is אַמָּה, ammah (Strong's H520). Strong's Hebrew Dictionary describes it as “properly, a mother” and then the forearm below the elbow, a cubit. It belongs to the same family of words as אֵם, em, “mother.” The measure was taken from the human body itself.
Noah's ark
And you shall make it this way: The length of the ark shall be three hundred cubits, its breadth fifty cubits, and its height thirty cubits.
Genesis 6:15 (KJ3)
At 18 inches to the cubit, 300 × 50 × 30 cubits is 450 feet long, 75 feet wide and 45 feet high (about 137 × 23 × 14 meters). Its length is six times its width.
The ark of the covenant
And they shall make an ark [of] acacia wood, two and a half cubits long, and a cubit and a half its width and a cubit and a half its height.
Exodus 25:10 (KJ3)
Two and a half by one and a half by one and a half cubits is 3 feet 9 inches long, 2 feet 3 inches wide and 2 feet 3 inches high.
The house Solomon built
As to the house that King Solomon built for Jehovah, its length [was] sixty cubits, its breadth twenty, and its height thirty cubits.
1 Kings 6:2 (KJ3)
Sixty by twenty by thirty cubits is 90 feet long, 30 feet wide and 45 feet high.
Goliath
And a man between the two came out from the armies of the Philistines, Goliath was his name, from Gath; his height was six cubits and a span.
1 Samuel 17:4 (KJ3)
A span is half a cubit, the width of the spread hand from thumb to little finger (the breastpiece of judgment was a span long and a span wide, Exodus 28:16). Six cubits and a span is six and a half cubits: about 9 feet 9 inches using the 18-inch cubit.
At a glance
| What was measured | In cubits | In feet (18-inch cubit) | Scripture |
|---|---|---|---|
| Noah's ark | 300 × 50 × 30 | 450 × 75 × 45 ft | Genesis 6:15 |
| The house Solomon built | 60 × 20 × 30 | 90 × 30 × 45 ft | 1 Kings 6:2 |
| Og's iron bedstead | 9 × 4 | 13.5 × 6 ft | Deuteronomy 3:11 |
| Goliath's height | 6½ | 9.75 ft | 1 Samuel 17:4 |
| The ark of the covenant | 2½ × 1½ × 1½ | 3.75 × 2.25 × 2.25 ft | Exodus 25:10 |
Measure your own cubit
Rest your elbow on a table, stretch out your fingers, and measure from the point of the elbow to the tip of the middle finger.
Challenge: the volume of the ark
Multiply length × width × height to find the volume of Noah's ark in cubic cubits, then convert it to cubic feet. At 1.5 feet to the cubit, one cubic cubit is 1.5 × 1.5 × 1.5 = 3.375 cubic feet.
The Shekel
The shekel was a weight before it was ever a coin: silver and gold were weighed out on balances. The shekel is usually reckoned at about 11.4 grams (roughly 0.4 ounce). The law fixed it at twenty gerahs:
They shall give this, everyone passing over to those numbered: half a shekel, by the shekel of the sanctuary, twenty gerahs [being] a shekel; half a shekel as an offering to Jehovah.
Exodus 30:13 (KJ3)
And all your evaluation shall be by the shekel of the sanctuary; twenty gerahs shall be the shekel.
Leviticus 27:25 (KJ3)
When Abraham bought the field of Machpelah, the silver was weighed, not counted:
And Abraham listened to Ephron, and Abraham weighed to Ephron the silver of which he had spoken in the ears of the sons of Heth, four hundred silver shekels which [passes] with the merchant.
Genesis 23:16 (KJ3)
Four hundred shekels at 11.4 grams each is about 4.6 kilograms (roughly 10 pounds) of silver.
The Ephah
The ephah was a dry measure for grain and flour. Estimates of its size vary; a commonly used figure is about 22 liters (roughly 5.8 US gallons, or about three-fifths of a bushel). Scripture gives its relation to the smaller omer and the larger homer:
And the omer [was] the tenth of an ephah.
Exodus 16:36 (KJ3)
The ephah and the bath [shall be] one measure, that the bath may contain the tenth of the homer, and the tenth of the homer the ephah. Its measure shall be to the homer.
Ezekiel 45:11 (KJ3)
So ten omers make an ephah, and ten ephahs make a homer. Ruth's day of gleaning came to about one ephah:
And she gleaned in the field until the evening, and beat out that which she had gleaned. And [it] was about an ephah of barley.
Ruth 2:17 (KJ3)
Practice
- Solomon's house was 60 cubits long. How many feet is that at 1.5 feet per cubit?
- A shipping container is 40 feet long. How many cubits is that?
- The ark of the covenant was 2½ × 1½ × 1½ cubits. What is its volume in cubic feet?
- How many grams of silver are in 50 shekels?
- Measure a doorway in your home. How many cubits high and wide is it?
Show answers
- 60 × 1.5 = 90 feet.
- 40 ÷ 1.5 ≈ 26.7 cubits.
- 2.5 × 1.5 × 1.5 = 5.625 cubic cubits; 5.625 × 3.375 ≈ 19 cubic feet.
- 50 × 11.4 = 570 grams.
- A standard 80-inch door is about 4.4 cubits high (80 ÷ 18).