Biblical Unit Converter
Convert ancient units mentioned in Scripture — length, weight, volume, New Testament coinage, and time-of-day — to modern equivalents.
Modern equivalent
About biblical measurements
The Bible uses units of length (like the cubit, roughly the distance from elbow to fingertip), weight (like the shekel, originally a weight before it became a coin name), and volume (like the ephah for dry goods and the bath for liquids) that don't map neatly onto modern feet, pounds, and liters. Scholars reconstruct approximate modern equivalents from archaeological finds (inscribed weights, measuring vessels) and comparison across ancient Near Eastern sources, but exact values shifted somewhat over the roughly 1,500 years the Bible was written across, and between the "royal" cubit used for major building projects and the shorter "common" cubit used day to day.
The figures in this converter follow the approximate values most commonly printed in modern study Bible footnotes and Bible dictionaries — useful for picturing scale (how big was Noah's ark, how much grain was an ephah) rather than for archaeological precision.
New Testament coinage worked on its own relative scale rather than a modern exchange rate: a denarius was a laborer's typical daily wage (Matthew 20:2), a didrachma covered one person's annual temple tax and a stater covered two (Matthew 17:24-27), and a mina and talent were much larger sums used in parables about money entrusted to servants (Luke 19; Matthew 25). This converter expresses every coin as a multiple of that one day's wage, which stays meaningful even though a dollar figure for "a denarius" would not. Biblical time divisions worked differently too — daytime was commonly divided into 12 hours from sunrise to sunset (so length varied by season), and the night into watches: three watches of about four hours in the Old Testament era, four watches of about three hours under the Roman system used in the Gospels.
Frequently asked questions
How long is a cubit?
About 18 inches (0.46 m) — roughly the length from an adult's elbow to fingertip, which is where the unit gets its name. Some building projects used a slightly longer "royal cubit" of about 20.4 inches, but 18 inches is the standard approximation used across most Bible measurement footnotes.
How much is a shekel in today's money?
A shekel was originally a unit of weight (about 0.4 oz / 11.4 g) for silver or gold, not a coin — its dollar value depends on the current price of that metal, not a fixed historical rate. This converter gives you the weight; multiplying by today's silver or gold spot price gives a rough modern value.
Why do the numbers vary between sources?
Ancient measurements weren't standardized the way metric or imperial units are today, and archaeologists have found measuring weights and vessels that differ somewhat by period and region. Different study Bibles and reference works round slightly differently as a result — this tool uses the most commonly cited approximations.
Why is New Testament currency shown as "day's wages" instead of dollars?
A denarius's actual purchasing power in today's dollars has no stable answer — prices and wages have changed too much over two thousand years for that conversion to mean anything reliable. What is well documented is how the coins related to each other and to ordinary daily life: a denarius was a laborer's typical day's wage (Matthew 20:2), so expressing every coin as a multiple of that gives a sense of scale that stays accurate.
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