Pound per Square Inch to Megapascal Converter
Convert pounds per square inch to megapascals with our free online pressure converter.
Quick Answer
1 Pound per Square Inch = 0.006895 megapascals
Formula: Pound per Square Inch × conversion factor = Megapascal
Use the calculator below for instant, accurate conversions.
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All conversion formulas on UnitsConverter.io have been verified against NIST (National Institute of Standards and Technology) guidelines and international SI standards. Our calculations are accurate to 10 decimal places for standard conversions and use arbitrary precision arithmetic for astronomical units.
Pound per Square Inch to Megapascal Calculator
How to Use the Pound per Square Inch to Megapascal Calculator:
- Enter the value you want to convert in the 'From' field (Pound per Square Inch).
- The converted value in Megapascal will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Pressure category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Pound per Square Inch to Megapascal: Step-by-Step Guide
Converting Pound per Square Inch to Megapascal involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
MPa = psi × 0.00689476Example Calculation:
1 psi = 0.006895 MPa
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
Need to convert to other pressure units?
View all Pressure conversions →What is a Pound per Square Inch and a Megapascal?
PSI (pounds per square inch) is a unit of pressure expressing force in pounds-force distributed over an area of one square inch. One PSI equals approximately 6,894.76 Pascals or 0.0689 bar.
Key conversions:
- 1 PSI = 6,894.76 Pa (Pascals)
- 1 PSI = 6.895 kPa (Kilopascals)
- 1 PSI = 0.0689 bar
- 14.7 PSI = 1 atmosphere (atm)
- Convert instantly with our PSI to bar converter
Important distinction:
- PSIG (gauge pressure): Relative to atmospheric pressure (0 PSIG = atmospheric)
- PSIA (absolute pressure): Relative to perfect vacuum
- Most pressure gauges show PSIG
1 MPa = 1,000,000 Pa = 1,000 kPa = 145.038 PSI = 10 bar = 9.869 atm
Why Megapascal?
MPa is the "sweet spot" for engineering pressures:
- Pascal is too small: 1 Pa = barely measurable (atmospheric is 101,325 Pa)
- Kilopascal is too granular: Engineering specs in kPa are 4-5 digit numbers (20,000 kPa for concrete)
- MPa is optimal: Concrete 20-40 MPa (simple, memorable)
- Engineering standard: All material specs given in MPa
- SI-derived: ISO and international standards use MPa
Note: The Pound per Square Inch is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Megapascal belongs to the imperial/US customary system.
Common Uses and Applications: pounds per square inch vs megapascals
Explore the typical applications for both Pound per Square Inch (imperial/US) and Megapascal (imperial/US) to understand their common contexts.
Common Uses for pounds per square inch
Automotive Industry
Primary pressure unit for tire inflation, fuel injection systems, turbo boost pressure, brake systems, and hydraulic lifts throughout North America.
Manufacturing & Industry
Standard for hydraulic presses, pneumatic systems, compressors, pressure vessels, and industrial equipment specifications in the US.
Construction
Used for concrete pumps, hydraulic tools, pneumatic nailing equipment, sandblasting, and compressed air systems.
HVAC & Refrigeration
Universal unit for refrigerant pressures, duct static pressure, gas line pressure, and system diagnostics in US HVAC industry.
Plumbing
Standard for water pressure measurements, pressure regulators, well pumps, and municipal water systems in the United States.
When to Use megapascals
Materials Engineering: Tensile strength, compressive strength, yield strength - THE standard unit for all material properties. Hydraulics: High-pressure hydraulic systems (construction, manufacturing, heavy equipment). Pressure Vessels: Gas cylinders, boilers, reactors, automotive fuel systems. Geotechnical: Soil bearing capacity, rock strength, foundation design. Aerospace: Structural requirements, component ratings.
Material Strengths (Compressive/Tensile)
Understanding material strength is critical for engineering design:
| Material | Type | Strength (MPa) | Notes | |---|---|---|---| | Styrofoam | Compression | 0.01-0.1 | Very weak, insulation only | | Wood (softwood) | Compression | 20-40 | Pine, spruce, fir typical | | Wood (hardwood) | Compression | 40-60 | Oak, maple stronger | | Brick | Compression | 10-40 | Varies by firing temperature | | Concrete (standard) | Compression | 20-40 | Common 28-day strength | | Concrete (high-strength) | Compression | 50-100 | Pre-stressed applications | | Granite | Compression | 100-250 | Very strong, suitable for columns | | Aluminum alloy (6061) | Tensile | 200-300 | Common structural aluminum | | Aluminum alloy (7075) | Tensile | 500-600 | High-strength aerospace | | Steel (structural ASTM A36) | Yield | 250 | Common building steel | | Steel (high-strength ASTM A572) | Yield | 345-450 | Bridge, crane applications | | Steel (ultra-high) | Tensile | 500-1,000 | Special applications | | Steel cable (wire rope) | Tensile | 1,600-2,000 | Elevators, suspension bridges | | Carbon fiber composite | Tensile | 3,000-7,000 | Aerospace, racing | | Kevlar fiber | Tensile | 3,600-3,800 | Armor, protective gear |
Design factor: Actual working stress = material strength ÷ safety factor (typically 2-4)
Hydraulic Systems (High Pressure)
Hydraulic pressure ratings define system capability:
| System Type | Operating Pressure | Peak Pressure | PSI Equivalent | Application | |---|---|---|---|---| | Automotive brake | 10-15 MPa | 20 MPa | 1,500-2,900 PSI | Car braking force | | Automobile power steering | 10-15 MPa | 20 MPa | 1,500-2,900 PSI | Steering assist | | Construction excavator | 20-35 MPa | 40 MPa | 2,900-5,800 PSI | Digging bucket | | Backhoe | 25-30 MPa | 35 MPa | 3,625-5,075 PSI | Heavy lifting | | Dump truck bed | 20-25 MPa | 30 MPa | 2,900-4,350 PSI | Lifting load | | Industrial press | 20-40 MPa | 50 MPa | 2,900-7,250 PSI | Metal forming | | Hydraulic jack | 50-70 MPa | 80 MPa | 7,250-11,600 PSI | Lifting capability | | Water jet cutter | 200-400 MPa | 450 MPa | 29,000-65,000 PSI | Material cutting | | Oil well pump | 100-200 MPa | 250 MPa | 14,500-36,250 PSI | Deep well pressure |
Pressure Vessels & Storage
Pressure ratings determine safe working limits:
| Vessel Type | Typical Pressure | Material | Working PSIG | |---|---|---|---| | Compressed air tank | 0.8-1.0 MPa | Steel | 116-145 PSI | | Propane BBQ tank | 1.5-2.0 MPa | Steel | 218-290 PSI | | Scuba tank (full) | 20-30 MPa | Aluminum/Steel | 3,000-4,350 PSI | | Natural gas vehicle | 20-25 MPa | Composite | 3,000-3,625 PSI | | Hydrogen fuel cell | 35-70 MPa | Carbon fiber | 5,000-10,000 PSI | | Industrial gas cylinder | 15-20 MPa | Steel | 2,175-2,900 PSI | | Medical oxygen | 13.8-15 MPa | Aluminum | 2,000-2,175 PSI | | Nitrogen (instrument) | 10-13.8 MPa | Steel | 1,450-2,000 PSI |
Safety factor: Pressure vessels typically designed with 4:1 to 6:1 safety margin
Geotechnical Engineering (Soil/Rock)
Foundation and excavation design based on pressure ratings:
| Material/Condition | Bearing Capacity | Suitable For | Notes | |---|---|---|---| | Soft clay | 0.05-0.2 MPa | Temporary structures | High settlement risk | | Medium clay | 0.1-0.3 MPa | Single story | Careful design needed | | Stiff clay | 0.3-0.5 MPa | Multi-story buildings | Good load capacity | | Dense sand | 0.3-0.6 MPa | Foundation base | Excellent for building | | Gravel/sand mixture | 0.6-1.0 MPa | Heavy structures | Very good bearing | | Soft rock (shale) | 1-10 MPa | Bridge supports | Rock analysis needed | | Medium rock | 10-50 MPa | Tall buildings | High capacity | | Hard rock (granite) | 50-100+ MPa | Largest structures | Excellent foundation |
Design process: Site investigation → soil tests → pressure capacity → foundation design
Additional Unit Information
About Pound per Square Inch (psi)
What is a good PSI for car tires?
Standard car tire pressure: 32-35 PSI (when cold)
Always check your specific vehicle:
- Driver's door jamb sticker (most reliable)
- Owner's manual
- Fuel filler door (some vehicles)
By vehicle type:
- Compact cars: 30-33 PSI
- Sedans: 32-35 PSI
- SUVs/Light trucks: 35-45 PSI
- High-performance: 36-40 PSI
Important: Check when tires are COLD (before driving). Tire pressure increases 4-6 PSI after driving.
Convert to your region: PSI to Bar →
How do I convert PSI to bar?
Formula: Bar = PSI × 0.0689476 (or divide PSI by 14.5)
Examples:
- 10 PSI = 0.69 bar
- 30 PSI = 2.07 bar
- 50 PSI = 3.45 bar
- 100 PSI = 6.89 bar
Quick mental math: Divide PSI by 14.5 or 15
- 30 PSI ÷ 15 ≈ 2 bar (actual: 2.07)
Use our PSI to Bar converter →
What does PSIG vs PSIA mean?
PSIG (Pounds per Square Inch Gauge):
- Pressure relative to atmospheric pressure
- 0 PSIG = atmospheric pressure (14.7 PSIA at sea level)
- What most pressure gauges show
- Used for tires, compressors, hydraulics
PSIA (Pounds per Square Inch Absolute):
- Pressure relative to perfect vacuum
- 0 PSIA = absolute vacuum
- 14.7 PSIA = atmospheric pressure at sea level
- Used in scientific/engineering calculations
Conversion: PSIA = PSIG + 14.7 (at sea level)
Example: 32 PSIG tire pressure = 46.7 PSIA total pressure
What is 100 PSI in bar and kPa?
100 PSI equals:
- 6.89 bar
- 689.5 kPa (kilopascals)
- 0.689 MPa (megapascals)
Quick conversions:
Context: 100 PSI is typical for:
- Heavy-duty air compressor output
- Semi-truck tire pressure
- Pneumatic tool operating pressure
Is 40 PSI good tire pressure?
40 PSI can be correct depending on your vehicle:
Good for:
- Large SUVs and trucks
- Some high-performance vehicles
- Vehicles when fully loaded
Too high for:
- Most passenger cars (typically 32-35 PSI)
- Compact cars (typically 30-33 PSI)
How to know:
- Check driver's door jamb sticker
- Consult owner's manual
- Never rely on tire sidewall (that's MAX pressure)
Effects of overinflation:
- Harsher ride
- Reduced traction
- Uneven tire wear (center wears faster)
Always check: When tires are COLD, before driving.
How many PSI in 1 atmosphere?
1 atmosphere (atm) = 14.6959 PSI (approximately 14.7 PSI)
Standard atmospheric pressure at sea level:
- 14.696 PSI (PSIA)
- 101.325 kPa
- 1.01325 bar
- 760 mmHg / 760 Torr
- 29.92 inHg
Altitude effects:
- Sea level: 14.7 PSI
- Denver (5,280 ft): ~12.1 PSI
- 10,000 ft: ~10.1 PSI
What PSI should I set my air compressor to?
Typical settings:
General Shop Use: 90-100 PSI
- Most pneumatic tools operate best at 90 PSI
- Allows for pressure drop in hoses
Specific Applications:
- Impact wrench: 90 PSI
- Nail gun: 70-120 PSI (tool dependent)
- Paint sprayer: 25-50 PSI
- Tire inflation: 30-40 PSI
- Sandblasting: 80-100 PSI
- Air brush: 15-30 PSI
Compressor tank pressure: 125-150 PSI (maximum)
- Compressor cuts off at max (e.g., 135 PSI)
- Compressor cuts on when drops (e.g., 100 PSI)
- Set regulator to desired tool pressure (e.g., 90 PSI)
Pro tip: Set higher tank pressure, use regulator for precise tool pressure.
Why is PSI used instead of bar in the US?
Historical reasons:
- Imperial system was established before metric
- US industry standardized on PSI in early 1900s
- Extensive infrastructure built around imperial units
Practical resistance to change:
- All existing gauges, equipment use PSI
- Workforce trained in PSI
- Replacement costs would be enormous
- Cultural familiarity
Current situation:
- US is primary country still using PSI
- Scientific/international work uses metric (bar, kPa)
- Some US industries use both systems
For travelers: Most modern tire gauges show both PSI and bar.
About Megapascal (MPa)
How do I convert MPa to PSI?
Formula: PSI = MPa × 145.038
Examples:
- 1 MPa = 145 PSI
- 10 MPa = 1,450 PSI (car brakes)
- 20 MPa = 2,900 PSI (hydraulic tools)
- 30 MPa = 4,350 PSI (scuba tank)
- 70 MPa = 10,153 PSI (H2 fuel tank)
What is concrete strength in MPa?
Residential concrete: 20-32 MPa (2,900-4,650 PSI)
- Footings/slabs: 20-25 MPa
- Foundation walls: 25-30 MPa
- Driveway: 25-32 MPa
Commercial concrete: 30-50 MPa
- Floors: 30-35 MPa
- Beams/columns: 35-50 MPa
High-strength: 50-100+ MPa
- High-rise buildings: 50-80 MPa
- Bridges: 60-100 MPa
- Special applications: 100-150 MPa
Conversion: Divide PSI by 145 to get MPa (e.g., 3,000 PSI ≈ 21 MPa)
How do I convert MPa to bar?
Formula: bar = MPa × 10
Examples:
- 0.1 MPa = 1 bar
- 1 MPa = 10 bar
- 2 MPa = 20 bar
- 10 MPa = 100 bar
- 20 MPa = 200 bar (scuba tank)
What is a typical hydraulic system pressure?
Low pressure: 7-14 MPa (1,000-2,000 PSI)
- Automotive power steering: 8-12 MPa
- Light hydraulic lifts: 7-10 MPa
Medium pressure: 14-21 MPa (2,000-3,000 PSI)
- Construction equipment: 20-25 MPa
- Agricultural machinery: 14-20 MPa
- Automotive brakes: 10-15 MPa
High pressure: 21-35 MPa (3,000-5,000 PSI)
- Industrial presses: 25-35 MPa
- Heavy construction: 30-35 MPa
- Excavators: 30-35 MPa
Very high pressure: >35 MPa (>5,000 PSI)
- Hydraulic jacks: 50-70 MPa
- Specialized industrial: 70-100 MPa
Why use MPa instead of PSI for material strength?
SI standard: International engineering uses MPa universally Simpler numbers: 400 MPa vs 58,000 PSI Scientific: Consistent with stress calculations (force/area in N/m²) Global: Specifications understood worldwide
Conversion: PSI ÷ 145 ≈ MPa (or PSI × 0.00689 = MPa)
Example: Steel yield strength
- As MPa: 250-400 MPa (easy)
- As PSI: 36,000-58,000 PSI (unwieldy)
Conversion Table: Pound per Square Inch to Megapascal
| Pound per Square Inch (psi) | Megapascal (MPa) |
|---|---|
| 0.5 | 0.003 |
| 1 | 0.007 |
| 1.5 | 0.01 |
| 2 | 0.014 |
| 5 | 0.035 |
| 10 | 0.069 |
| 25 | 0.172 |
| 50 | 0.345 |
| 100 | 0.69 |
| 250 | 1.724 |
| 500 | 3.447 |
| 1,000 | 6.895 |
People Also Ask
How do I convert Pound per Square Inch to Megapascal?
To convert Pound per Square Inch to Megapascal, enter the value in Pound per Square Inch in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our pressure converter page to convert between other units in this category.
Learn more →What is the conversion factor from Pound per Square Inch to Megapascal?
The conversion factor depends on the specific relationship between Pound per Square Inch and Megapascal. You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.
Can I convert Megapascal back to Pound per Square Inch?
Yes! You can easily convert Megapascal back to Pound per Square Inch by using the swap button (⇌) in the calculator above, or by visiting our Megapascal to Pound per Square Inch converter page. You can also explore other pressure conversions on our category page.
Learn more →What are common uses for Pound per Square Inch and Megapascal?
Pound per Square Inch and Megapascal are both standard units used in pressure measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our pressure converter for more conversion options.
For more pressure conversion questions, visit our FAQ page or explore our conversion guides.
Helpful Conversion Guides
Learn more about unit conversion with our comprehensive guides:
📚 How to Convert Units
Step-by-step guide to unit conversion with practical examples.
🔢 Conversion Formulas
Essential formulas for pressure and other conversions.
⚖️ Metric vs Imperial
Understand the differences between measurement systems.
⚠️ Common Mistakes
Learn about frequent errors and how to avoid them.
All Pressure Conversions
Other Pressure Units and Conversions
Explore other pressure units and their conversion options:
- Pascal (Pa) • Pound per Square Inch to Pascal
- Kilopascal (kPa) • Pound per Square Inch to Kilopascal
- Hectopascal (hPa) • Pound per Square Inch to Hectopascal
- Bar (bar) • Pound per Square Inch to Bar
- Millibar (mbar) • Pound per Square Inch to Millibar
- Atmosphere (atm) • Pound per Square Inch to Atmosphere
- Technical Atmosphere (at) • Pound per Square Inch to Technical Atmosphere
- Torr (Torr) • Pound per Square Inch to Torr
- Millimeter of Mercury (mmHg) • Pound per Square Inch to Millimeter of Mercury
- Inch of Mercury (inHg) • Pound per Square Inch to Inch of Mercury
Verified Against Authority Standards
All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.
National Institute of Standards and Technology — Fundamental physical constants and unit conversions
Bureau International des Poids et Mesures — International System of Units (SI) definitions and standards
International Organization for Standardization — Quantities and units international standards series
Last verified: February 19, 2026