Kilometer/Hour to Kilometer/Second Converter
Convert Kilometer/Hour (km/h) to Kilometer/Second (km/s) instantly. 1 km/h = 0.000278 km/s.
Speed Converter
18 units available
1 km/h = 0.000278 km/s
Formula:
km/s = km/h × 0.0002777778With your value: 1 km/h = 0.00027778 km/s
How big is that?
Everyday references on a logarithmic scale, all expressed in kilometer/hour so you can sanity-check the result.
Other Kilometer/Hour to Kilometer/Second conversions
Kilometer/Hour to Kilometer/Second Conversion Table
| Kilometer/Hour (km/h) | Kilometer/Second (km/s) |
|---|---|
| 0.5 | 0.000139 |
| 1 | 0.000278 |
| 2 | 0.000556 |
| 5 | 0.001389 |
| 10 | 0.002778 |
| 15 | 0.004167 |
| 20 | 0.005556 |
| 25 | 0.006944 |
| 50 | 0.013889 |
| 100 | 0.027778 |
| 250 | 0.069444 |
| 500 | 0.138889 |
| 1000 | 0.277778 |
Kilometer/Second to Kilometer/Hour Conversion Table
| Kilometer/Second (km/s) | Kilometer/Hour (km/h) |
|---|---|
| 0.5 | 1,800 |
| 1 | 3,600 |
| 2 | 7,200 |
| 5 | 18,000 |
| 10 | 36,000 |
| 15 | 54,000 |
| 20 | 72,000 |
| 25 | 90,000 |
| 50 | 180,000 |
| 100 | 360,000 |
| 250 | 900,000 |
| 500 | 1,800,000 |
| 1000 | 3,600,000 |
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.
Kilometer/Hour (km/h)
Speed
Derived quantity: a defined length divided by a defined time interval.
Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)
Bureau International des Poids et Mesures · Reviewed 2026-07-01
Kilometer/Second (km/s)
Speed
Derived quantity: a defined length divided by a defined time interval.
Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)
Bureau International des Poids et Mesures · Reviewed 2026-07-01
How to Convert Kilometer/Hour to Kilometer/Second
To convert from Kilometer/Hour (km/h) to Kilometer/Second (km/s), multiply the value by 0.0002777778.
Formula: km/s = km/h × 0.0002777778
Reverse: km/h = km/s × 3,600
Step-by-Step Example
- Start with your value in Kilometer/Hour. For example: 5 km/h
- Multiply by the conversion factor: 5 x 0.0002777778
- The result is: 0.001389 km/s
About Kilometer/Hour
Kilometers per hour is the most widely used unit of speed for vehicles in most countries.
Common uses: speed limits, vehicle speed, weather.
About Kilometer/Second
The kilometer/second (km/s) is a unit of speed and velocity. One kilometer/second equals 1000 metre per seconds. UnitConvertLab converts it against every other speed unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
Common uses: speed calculations, engineering and science, education.
Frequently Asked Questions
How many Kilometer/Second are in 1 Kilometer/Hour?
There are exactly 0.0002777778 Kilometer/Second in 1 Kilometer/Hour. This means the conversion factor from Kilometer/Hour to Kilometer/Second is 0.0002777778.
What is the formula to convert Kilometer/Hour to Kilometer/Second?
The formula to convert Kilometer/Hour to Kilometer/Second is: km/s = km/h × 0.0002777778. For example, to convert 10 Kilometer/Hour to Kilometer/Second, you would multiply 10 by 0.0002777778.
What is a Kilometer/Hour?
Kilometers per hour is the most widely used unit of speed for vehicles in most countries.
What is a Kilometer/Second?
The kilometer/second (km/s) is a unit of speed and velocity. One kilometer/second equals 1000 metre per seconds. UnitConvertLab converts it against every other speed unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
What are the common uses of Kilometer/Hour?
The Kilometer/Hour is commonly used in speed limits, vehicle speed, weather.
Related Speed Conversions
Cite this page
UnitConvertLab. (2026). Kilometer/Hour to Kilometer/Second converter. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/kmph-to-kmps