Cubits to Feet Converter
Using the standard cubit of 18 inches (1.5 ft). Other cubits differed — see below.
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The cubit was never standardised. This converter uses the common 18-inch cubit; Egyptian, Roman and biblical cubits all differed.
A unit measured on a forearm
The cubit is one of the oldest recorded units of length: the distance from the elbow to the tip of the middle finger. Because forearms vary, so did the cubit — and that is the single most important thing to know before converting one.
1 cubit = 18 in = 1.5 ft (the standard cubit)
The figures actually used in history:
- Common Egyptian cubit — about 45 cm (1.48 ft)
- Egyptian royal cubit — about 52.4 cm (1.72 ft), seven palms rather than six
- Roman cubit — about 44.4 cm (1.46 ft)
- Standard or short cubit — 18 inches (1.5 ft), the figure used here
So any conversion of a historical measurement is an estimate. Noah's ark at 300 cubits is 450 feet on the standard cubit and about 515 feet on the royal one — a difference of more than a fifth.
The cubit
One of the oldest recorded units, measured from the elbow to the tip of the middle finger. Because forearms vary, so did the cubit — the Egyptian royal cubit was about 52.4 cm, the common Egyptian cubit about 45 cm, the Roman cubit around 44.4 cm.
This converter uses the standard cubit of 18 inches, or 45.72 centimetres, which is the figure most commonly used when reading historical and biblical measurements. Treat any cubit figure as approximate: the unit was never standardised in the way a metre is.
The foot
Twelve inches, and exactly 0.3048 metres by international agreement. The twelve is the useful part: it divides by 2, 3, 4 and 6, which is easier for dividing a length by eye than a base-ten unit.
It remains standard for human height, building dimensions and aviation altitude — flight levels are in feet almost everywhere in the world, including countries that use metres for everything else.
The working, step by step
Every line updates with whatever you type above. The point is the method, which is the same for any pair of units in this family.
The same quantity, two different numbers
One physical amount, read off two scales. The tick marks do not line up, and the gap between them is the conversion factor made visible.
How much is that?
A number is easier to judge next to something familiar.
Your turn
Reading a method and being able to use it are different things. Answer within half a per cent and it counts as correct.
Score: 0 of 0
How to use this converter
- Type into either box. The other side updates as you go; there is no button to press.
- Swap the direction with the button between the boxes, carrying your value across.
- Set the decimals if the default is more or less precision than you need.
- Copy the answer with its unit, ready to paste.
- Use the shortcut buttons for the values that come up most often.
- Share the result. The address bar tracks what you type, so the link you copy opens on the same number.
Common uses and tips
Where length conversions come up
- Height. Quoted in feet and inches in Britain and America, and in centimetres nearly everywhere else. 5 ft 10 in is 178 cm.
- Buying things online from another market, where the dimensions are in units your tape measure does not have.
- DIY and building, where materials come in metric sizes and older plans are in imperial.
- Screens, tyres and pipes, which stay in inches worldwide even in fully metric countries.
- Running and cycling, where race distances are metric and training apps may report either.
Numbers worth carrying
- 1 inch = 2.54 cm exactly. Everything imperial in this family descends from it.
- 1 foot = 30.48 cm, twelve inches.
- 1 yard = 0.9144 m, a little shorter than a metre.
- 1 mile = 1.609 km, and 1 km = 0.621 mile.
- A metre is about 39.37 inches, or 3 ft 3 in.
Mental shortcuts
Kilometres to miles: multiply by six and drop the last digit. 80 km × 6 = 480, drop the digit for 48 miles, against a true 49.7.
Miles to kilometres: add sixty per cent. 50 miles plus 60 % is 80 km, against a true 80.5.
Centimetres to inches: divide by 2.5 and take off a little. Dividing by 2.5 gives an answer about 1.6 % high.
Mistakes worth avoiding
- Feet and inches are not decimal. 5.5 feet is 5 ft 6 in, not 5 ft 5 in. Multiply the decimal part by twelve.
- Do not use length factors for area or volume. A foot is 0.3048 m, but a square foot is 0.0929 m² and a cubic foot 0.0283 m³.
- Check which mile. A nautical mile is 1,852 m, about 15 % longer than a statute mile.
Values people look up most
Each one opens the converter with the number already in it.
- 1 cubit to ft
- 2 cubit to ft
- 3 cubit to ft
- 5 cubit to ft
- 10 cubit to ft
- 20 cubit to ft
- 50 cubit to ft
- 100 cubit to ft
- 150 cubit to ft
- 200 cubit to ft
- 300 cubit to ft
- 450 cubit to ft
Quick reference
| Cubits | Feet |
|---|---|
| 1 cubit | 1.5 ft |
| 2 cubit | 3 ft |
| 5 cubit | 7.5 ft |
| 10 cubit | 15 ft |
| 50 cubit | 75 ft |
| 100 cubit | 150 ft |
| 300 cubit | 450 ft |
Questions people ask
How long is a cubit?
Traditionally 18 inches, but it varied. The Egyptian royal cubit was about 20.6 inches.
Which cubit does this use?
The standard 18-inch cubit, which is the figure most often used for biblical and historical measurements.
How long was Noah's ark in feet?
300 cubits is 450 ft using the standard cubit, or about 515 ft using the Egyptian royal cubit.
Why did the cubit vary so much?
Because it was defined by the human body rather than by a physical standard, and different civilisations fixed it differently.