Kilopascal (kPa) - Unit Information & Conversion
🔄 Quick Convert Kilopascal
What is a Kilopascal?
Kilopascal (kPa) = 1,000 pascals. International standard for tire pressure, weather reporting, engineering. More practical than pascals. 1 kPa = 0.145 PSI. Car tires: 220-240 kPa (32-35 PSI). Sea level: 101.325 kPa.
History of the Kilopascal
Derived from pascal (SI pressure unit, 1971). Kilo prefix makes measurements practical since 1 Pa is very small. Standard worldwide except USA for tire pressure, medical blood pressure equipment, industrial specifications.
Quick Answer
What is a Kilopascal? Kilopascal (kPa) = 1,000 pascals. International standard for tire pressure, blood pressure devices, engineering. 1 kPa = 0.145 PSI = 0.01 bar. Car tires: 220-240 kPa (32-35 PSI). Atmospheric pressure: ~101 kPa. Use our pressure converter for conversions.
Key Facts: Kilopascal
| Property | Value |
|---|---|
| Symbol | kPa |
| Quantity | Pressure |
| System | Metric/SI Derived |
| Derived from | Pascal |
| Category | Pressure |
| Standard Body | NIST / ISO |
Definition
1 kPa = 1,000 Pa = 0.145038 PSI = 0.01 bar = 10 hPa = 10 mbar = 0.00987 atm = 7.5 mmHg
Why Kilopascal?
The kilopascal is the practical SI unit for everyday pressures:
- Pascal is too small: 1 Pa = fingernail scratch pressure (not useful)
- Megapascal is too large: 1 MPa = industrial level (uncommon for most uses)
- Kilopascal is "just right": 100-300 kPa range covers most everyday pressures
- SI standard: International standard for tire pressure, medical, engineering
- Clean conversions: Exactly 0.145 PSI, exactly 0.01 bar
Common Uses
Automotive: Tire pressure (international standard, except USA).
- Car manufacturers specify tire pressure in kPa on door jamb
- Repair manuals use kPa
- Tire pressure gauges often have kPa scale
Medical: Blood pressure equipment (replacing mmHg in some regions).
- Modern digital blood pressure monitors often display kPa
- Medical research uses kPa
- Gradual transition from mmHg (some regions still use mmHg)
Meteorology: Atmospheric pressure (101.325 kPa at sea level).
- European weather reports sometimes use kPa
- Upper atmosphere measurements in kPa
- Pressure profiling in meteorology
Engineering: Structural loads, material strength, HVAC systems.
- Material testing: tensile strength in MPa, stress in kPa
- Building code pressure ratings in kPa
- Water system specifications in kPa
Real-World Examples
Tire Pressures (Different Vehicle Types)
Understanding proper tire pressure is critical for:
- Fuel efficiency: Underinflated tires increase rolling resistance
- Safety: Both overinflation and underinflation reduce traction
- Tire life: Improper pressure causes uneven wear
| Vehicle Type | Pressure | PSI | Notes |
|---|---|---|---|
| Road bicycle | 600-800 kPa | 87-116 | High pressure for low rolling resistance |
| Mountain bicycle | 200-300 kPa | 29-44 | Lower for traction/comfort on rough terrain |
| Motorcycle | 200-290 kPa | 29-42 | Hot tire pressure 10-20 kPa higher |
| Compact car | 210-230 kPa | 30-33 | Check door jamb for manufacturer spec |
| Sedan | 220-240 kPa | 32-35 | Most common range |
| SUV/Crossover | 230-250 kPa | 33-36 | Higher due to vehicle weight |
| Light truck | 240-280 kPa | 35-40 | Depends on load |
| Heavy truck | 550-900 kPa | 80-130 | Separate pressures for steering/drive wheels |
| Aircraft tire | 1,200-1,600 kPa | 175-230 | Extremely high for load-bearing |
| Forklift | 300-600 kPa | 43-87 | Depends on weight capacity |
Important: Always check manufacturer specification on vehicle door jamb; tire sidewall pressure is maximum, not recommended!
Blood Pressure Measurements
Blood pressure readings are pressure in arteries:
| Category | Systolic/Diastolic (mmHg) | Systolic/Diastolic (kPa) | Meaning |
|---|---|---|---|
| Normal | <120 / <80 | <16.0 / <10.7 | Healthy, no action needed |
| Elevated | 120-129 / <80 | 16-17.2 / <10.7 | Borderline, lifestyle changes |
| Hypertension Stage 1 | 130-139 / 80-89 | 17.3-18.5 / 10.7-11.9 | Medical attention recommended |
| Hypertension Stage 2 | ≥140 / ≥90 | ≥18.7 / ≥12.0 | Medical treatment typically needed |
| Hypertensive Crisis | >180 / >120 | >24 / >16 | Seek emergency care |
Conversion: 1 mmHg ≈ 0.1333 kPa
Atmospheric Pressure at Various Altitudes
| Location | Altitude | Pressure (kPa) | % of Sea Level |
|---|---|---|---|
| Sea level | 0m | 101.325 | 100% |
| Denver | 1,609m | 83.5 | 82% |
| Mexico City | 2,240m | 76.5 | 75% |
| La Paz, Bolivia | 3,640m | 64.5 | 64% |
| Mount Kilimanjaro | 5,895m | 54.4 | 54% |
| Lhasa, Tibet | 3,656m | 64.3 | 63% |
| Mount Everest | 8,848m | 33.7 | 33% |
| Concorde cruise | 18,000m | 7.8 | 8% |
| Commercial jet | 10,000m | 26.5 | 26% (cabin ~61 kPa) |
Industrial and Engineering Applications
- Vacuum chambers (rough vacuum): 1-10 kPa
- Used for: Vacuum packaging, electron microscopy, space simulation
- HVAC ductwork pressure: 0.1-2.5 kPa
- Typical supply: 1-2 kPa (250-500 Pa static pressure)
- Residential: 0.1-0.5 kPa
- Commercial: 0.5-2.5 kPa
- Natural gas (residential): 1.75-7 kPa
- Typical: 1.75 kPa (25 PSI) at meter
- Water main pressure: 300-800 kPa (43-116 PSI)
- Minimum: 200 kPa (code requirement in many places)
- Optimal: 400-600 kPa
- Excess: >700 kPa (can damage fixtures)
- Compressed air (industrial): 600-1,000 kPa (87-145 PSI)
- Standard plant air: 700 kPa (100 PSI)
- Pneumatic tools: 600-700 kPa
- Hydraulic systems: 7,000-35,000 kPa (1,000-5,000 PSI)
- Excavator: 21,000-28,000 kPa
- Aircraft landing gear: 28,000 kPa
- Material testing machines: All measured in kPa or MPa
- Tensile strength testing
- Compression testing
- Yield point testing
Grand Technical Kilopascal Registry: Infrastructure Skyscraper
A massive registrar documenting 1000 unique kPa-scale pressure milestones across civil engineering and high-pressure logistics.
Civil Engineering & Structural Load Logs (kPa)
- kPaLog 1001: 10 kPa - Minimal ground pressure exerted by a specialized low-soil-impact agricultural tractor.
- kPaLog 1002: 25 kPa - Standard design bearing capacity for soft alluvial soil in suburban infrastructure logs.
- kPaLog 1003: 50 kPa - Estimated wind pressure on a high-rise glass facade during a localized gale-force event.
- kPaLog 1004: 100 kPa - Approximate atmospheric pressure at sea level, the fundamental benchmark for kPa metrics.
- kPaLog 1005: 150 kPa - Standard working pressure for a large-scale municipal water distribution main in urban hubs.
- kPaLog 1006: 200 kPa - Design pressure for an industrial-grade regional rainwater harvesting storage unit.
- kPaLog 1007: 350 kPa - Maximum safe operating pressure for a residential boiler system in metropolitan districts.
- kPaLog 1008: 500 kPa - Threshold for high-performance industrial fire suppression water delivery nodes.
- kPaLog 1009: 750 kPa - Pressure rating for a specialized heavy-duty hydraulic actuator in manufacturing rigs.
- kPaLog 1010: 1000 kPa - 1 MPa barrier, used for high-capacity pneumatic tools in professional aerospace labs.
Kilopascal Conversion Formulas
To Pascal:
To Megapascal:
To Hectopascal:
To Bar:
To Millibar:
To Atmosphere:
To Technical Atmosphere:
To Torr:
To Millimeter of Mercury:
To Inch of Mercury:
To Pound per Square Inch:
To Kilopound per Square Inch:
To Kilogram-force per Square Centimeter:
To Kilogram-force per Square Meter:
To Millimeter of Water Column:
To Inch of Water Column:
Frequently Asked Questions
Formula: PSI = kPa × 0.145038 (or kPa ÷ 6.895) Examples:
- 100 kPa = 14.5 PSI
- 200 kPa = 29 PSI (bicycle tire)
- 220 kPa = 32 PSI (typical car tire)
- 240 kPa = 35 PSI (SUV tire)
- 600 kPa = 87 PSI (road bike) kPa to PSI converter →
Convert Kilopascal
Need to convert Kilopascal to other pressure units? Use our conversion tool.