21 BTU/Second to Foot-Pound/Second
Quick answer
21 BTU/Second (BTU/s) equals
16,341.554508 ft·lbf/s
To convert 21 BTU/Seconds to Foot-Pound/Seconds, multiply by 778.169262284. Therefore, 21 BTU/Second (BTU/s) equals 16,341.554508 Foot-Pound/Second (ft·lbf/s).
Formula: ft·lbf/s = BTU/s × 778.169262284. Calculation: 21 × 778.169262284 = 16,341.554508 ft·lbf/s.
Convert BTU/Second (BTU/s) to Foot-Pound/Second (ft·lbf/s) online with our free unit converter. In power, 1 BTU/s = 778.169262 ft·lbf/s. Explore step-by-step conversion steps, mathematical formulas, and quick conversion reference tables below.
Worked example: converting BTU/Second to Foot-Pound/Second
- Step 1 — start with the formula. ft·lbf/s = BTU/s × 778.169262284
- Step 2 — substitute your figure. 21 BTU/s × 778.169262284
- Step 3 — read the result. 21 BTU/s = 16,341.554508 ft·lbf/s
- Step 4 — check it in reverse. BTU/s = ft·lbf/s × 0.0012850675 returns Invalid BTU/s, which matches the figure you started with.
Power Converter
22 units available
21 BTU/s = 16,341.554508 ft·lbf/s
Formula:
ft·lbf/s = BTU/s × 778.169262284With your value: 21 BTU/s = 16,341.55450796 ft·lbf/s
How big is that?
Everyday references on a logarithmic scale, all expressed in btu/second so you can sanity-check the result.
Other BTU/Second to Foot-Pound/Second conversions
BTU/Second to Foot-Pound/Second Conversion Table
| BTU/Second (BTU/s) | Foot-Pound/Second (ft·lbf/s) |
|---|---|
| 0.5 | 389.084631 |
| 1 | 778.169262 |
| 2 | 1,556.338525 |
| 5 | 3,890.846311 |
| 10 | 7,781.692623 |
| 15 | 11,672.538934 |
| 20 | 15,563.385246 |
| 25 | 19,454.231557 |
| 50 | 38,908.463114 |
| 100 | 77,816.926228 |
| 250 | 194,542.315571 |
| 500 | 389,084.631142 |
| 1000 | 778,169.262284 |
Foot-Pound/Second to BTU/Second Conversion Table
| Foot-Pound/Second (ft·lbf/s) | BTU/Second (BTU/s) |
|---|---|
| 0.5 | 0.000643 |
| 1 | 0.001285 |
| 2 | 0.00257 |
| 5 | 0.006425 |
| 10 | 0.012851 |
| 15 | 0.019276 |
| 20 | 0.025701 |
| 25 | 0.032127 |
| 50 | 0.064253 |
| 100 | 0.128507 |
| 250 | 0.321267 |
| 500 | 0.642534 |
| 1000 | 1.285067 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
BTU/Second (BTU/s)
Power
Derived from the watt (1 W = 1 J/s).
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
Foot-Pound/Second (ft·lbf/s)
Power
Derived from the watt (1 W = 1 J/s).
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
How to Convert BTU/Second to Foot-Pound/Second
To convert from BTU/Second (BTU/s) to Foot-Pound/Second (ft·lbf/s), multiply the value by 778.169262284.
Formula: ft·lbf/s = BTU/s × 778.169262284
Reverse: BTU/s = ft·lbf/s × 0.0012850675
Step-by-Step Example
- Start with your value in BTU/Second. For example: 5 BTU/s
- Multiply by the conversion factor: 5 x 778.169262284
- The result is: 3,890.846311 ft·lbf/s
BTU/Second and Foot-Pound/Second Relationship
Both BTU/Second and Foot-Pound/Second belong to the US Customary / Imperial system, making this an intra-system conversion within power. Since 1 BTU/Second equals approximately 778.1693 Foot-Pound/Seconds, the BTU/Second represents a larger unit interval than the Foot-Pound/Second. Understanding the relationship between BTU/Second and Foot-Pound/Second is essential for accurate calculations in physics, engineering, commerce, and daily applications.
About BTU/Second
The BTU/Second (symbol: BTU/s) is a recognized unit in the US Customary / Imperial measurement framework, utilized within power applications for precision and standardized data representation.
Common uses of BTU/Second: power calculations, engineering and science, education.
About Foot-Pound/Second
The Foot-Pound/Second (symbol: ft·lbf/s) is a recognized unit in the US Customary / Imperial measurement framework, utilized within power applications for precision and standardized data representation.
Common uses of Foot-Pound/Second: power calculations, engineering and science, education.
Frequently Asked Questions
- What is 21 BTU/Second in Foot-Pound/Second?
- 21 BTU/Second equals 16,341.554508 Foot-Pound/Second.
- How many Foot-Pound/Seconds are in 1 BTU/Second?
- There are exactly 778.169262284 Foot-Pound/Seconds in 1 BTU/Second. This means the conversion factor from BTU/Second to Foot-Pound/Second is 778.169262284.
- What is the formula to convert BTU/Second to Foot-Pound/Second?
- The formula to convert BTU/Second to Foot-Pound/Second is: ft·lbf/s = BTU/s × 778.169262284. For example, to convert 10 BTU/Seconds to Foot-Pound/Seconds, you would multiply 10 by 778.169262284.
- What is a BTU/Second?
- The BTU/Second (symbol: BTU/s) is a recognized unit in the US Customary / Imperial measurement framework, utilized within power applications for precision and standardized data representation.
- What is a Foot-Pound/Second?
- The Foot-Pound/Second (symbol: ft·lbf/s) is a recognized unit in the US Customary / Imperial measurement framework, utilized within power applications for precision and standardized data representation.
- What are the common uses of BTU/Second?
- The BTU/Second is commonly used in power calculations, engineering and science, education.
Related Power Conversions
Cite this page
UnitConvertLab. (2026). 21 BTU/Second to Foot-Pound/Second. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/21-btu_per_second-to-foot_pound_per_second