How many cubic feet are in one oil barrel?

One US oil barrel (bbl) equals exactly 42 US liquid gallons, which converts to approximately 5.614583 cubic feet.

Is this for US oil barrels or UK barrels?

This tool uses the US oil barrel (42 US gallons = 5.614583 ft³), which is the standard unit in the petroleum industry worldwide.

Can I convert barrels back to cubic feet?

Yes. Simply type your barrel value in the Barrels field and the converter immediately shows the equivalent in cubic feet.

Why is the oil barrel 42 gallons?

The 42-gallon standard was adopted by Pennsylvania oil producers in the 1860s, based on the old tierce wine barrel that held 42 gallons and allowed for transportation losses.

Is this the same as a beer barrel or wine barrel?

No. A US beer barrel is 31 gallons and a US wine barrel is typically 59.4 gallons. This tool uses the petroleum barrel of 42 US gallons.

Does this convert natural gas to barrels of oil equivalent (BOE)?

No. This tool calculates geometric fluid volume (1 bbl = 5.614583 ft³). Barrels of oil equivalent (BOE) is an energy metric where 1 BOE corresponds to roughly 5,800 standard cubic feet of natural gas based on heat content.

Cubic Feet to Barrels Converter

Convert cubic feet to oil barrels (bbl) or barrels back to cubic feet instantly.

Enter a Value

Cubic Feet (ft³)

Oil Barrels (bbl)

Result

Cubic Feet

—

ft³

Oil Barrels

—

bbl

Quick Reference

Cubic Feet (ft³)	Oil Barrels (bbl)
1	0.17811
5	0.89054
10	1.78107
50	8.90538
100	17.81076
1,000	178.10761
5,614.583	1,000

1 US oil barrel = 42 US gallons = 5.614583 ft³ (exact factor used in this tool)

Summary

This converter handles bidirectional conversion between cubic feet (ft³) and US oil barrels (bbl). One US oil barrel equals exactly 42 US gallons, which is approximately 5.614583 cubic feet. Use it for petroleum engineering, storage tanks, and liquid volume calculations. Note that energy-based barrel of oil equivalent (BOE) calculations for natural gas require heat-content conversion, not geometric volume.

How it works

Enter a value in either the cubic feet or barrels field.
The converter calculates the result in real time using the exact factor: 1 bbl = 5.614583 ft³.
Switch the direction of conversion by typing in the opposite field.
Use the swap button to flip the input and output fields.
Copy the result with the Copy button for use in reports or spreadsheets.

Use cases

Calculate storage tank capacity in barrels from measured cubic feet dimensions.
Convert drilling mud pit or storage vessel capacities between cubic feet and barrels.
Cross-check field measurements for petroleum engineers and surveyors.
Translate reported volumes between American and international petroleum reporting standards.
Estimate pipeline or vessel capacity for logistics planning.

Frequently Asked Questions

Last updated: 2026-10-05 · Reviewed by Nham Vu