Convert Megapascal to Inch of Mercury (MPainHg)

The megapascal is the engineering high-pressure unit, used in hydraulics, materials testing, and construction.

295.2998
1 MPa295.2998 inHgNIST · BIPM accuracy

Megapascal to Inch of Mercury Conversion Table

10 common values
MegapascalInch of Mercury
1 MPa295.2998 inHg
5 MPa1,476.499 inHg
10 MPa2,952.998 inHg
25 MPa7,382.495 inHg
50 MPa14,764.99 inHg
100 MPa29,529.98 inHg
200 MPa59,059.96 inHg
500 MPa147,649.9 inHg
1,000 MPa295,299.8 inHg
5,000 MPa1,476,499 inHg

How to Convert Megapascal to Inch of Mercury Manually

Step by Step

Converting megapascals to inches of mercury is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

  1. 1
    Take your value in megapascals
    Start with the number of megapascals (MPa) you want to convert.
  2. 2
    Multiply by 295.2998
    The conversion factor from MPa to inHg is 295.2998. Multiply your value by this number.
  3. 3
    Read the result in inches of mercury
    The result is your value in inches of mercury (inHg).
Practical Examples
1 MPa
equals
295.2998 inHg
5 MPa
equals
1,476.499 inHg
10 MPa
equals
2,952.998 inHg
25 MPa
equals
7,382.495 inHg
100 MPa
equals
29,529.98 inHg

Formula

Multiply the value in megapascals by 295.2998. For the reverse direction, multiply by 0.003386.

ForwardinHg = MPa × 295.2998
ReverseMPa = inHg × 0.003386
Example: 10 MPa × 295.2998 = 2,952.998 inHg

Tips

Use these in everyday conversions
  • 1 MPa = 10 bar = 145 psi.
  • N/mm² = MPa (same unit, different notation).
  • Use MPa for material science; bar for fluid dynamics.

Common Mistakes

Avoid these
  • Confusing MPa with MW or MJ.
  • Using 1 MPa = 100 bar — that's incorrect; it's 10 bar.
  • Mixing MPa and kPa without conversion in mixed docs.

About Megapascal and Inch of Mercury

What is the Megapascal?

The megapascal equals 1,000,000 pascals (or 10 bar) and is the engineering high-pressure unit used in hydraulics, materials testing, and construction. Concrete compressive strength is rated in MPa (typical residential concrete is 20–35 MPa, structural concrete 35–70 MPa, high-strength up to 140 MPa), and steel yield strengths are 250–700 MPa for structural grades. Hydraulic systems operate at 10–70 MPa, and high-pressure-water-jet cutting reaches 400 MPa. The megapascal is dimensionally identical to N/mm² (newtons per square millimeter), making it natural for engineering calculations involving small areas. Earth's mantle pressure reaches gigapascals (1 GPa = 1,000 MPa). The MPa relates to the pascal (10⁶ Pa = 1 MPa), the bar (10 bar = 1 MPa), the psi (1 MPa ≈ 145.04 psi), and the atmosphere (1 MPa ≈ 9.87 atm). It is the standard unit in modern engineering specifications worldwide.

  • Hydraulic system pressures
  • Concrete and steel strength specifications
  • High-pressure industrial processes
Real-world examples

Concrete compressive strength: 20–60 MPa. Hydraulic press: 30–70 MPa. Steel yield strength: 250+ MPa.

What is the Inch of Mercury?

The inch of mercury equals exactly 25.4 mmHg (or about 3,386.4 pascals) and is the American aviation standard for altimeter settings and historic barometer readings. Pilots set their altimeters to the local atmospheric pressure in inHg before takeoff and landing — standard 'sea-level pressure' is 29.92 inHg. American weather reports historically used inHg before transitioning to millibars/hPa, and home barometers in the US still display inHg. The unit relates to the mmHg (25.4 mmHg = 1 inHg), the millibar (1 inHg ≈ 33.864 mbar), the kilopascal (1 inHg ≈ 3.386 kPa), and the psi (1 inHg ≈ 0.491 psi). Aviation's continued use of inHg in the United States reflects regulatory tradition rather than scientific advantage; international ATC outside the US uses hectopascals.

  • US aviation altimeter QNH settings
  • US residential barometers
  • US weather forecasts (older)
Real-world examples

Sea-level standard: 29.92 inHg. Mountain pass at 3000 m: ~21 inHg. US aviation QNH given in inHg.

Learn About Both Units

🎈 Reference

What is the Megapascal?

Read the unit page →
🎈 Reference

What is the Inch of Mercury?

Read the unit page →

Megapascal to Inch of Mercury FAQ

5 questions
How many inches of mercury in a megapascal?
One megapascal equals 295.2998 inches of mercury.
How do I convert megapascals to inches of mercury?
Multiply the megapascal value by 295.2998 to get the equivalent in inches of mercury.
What is 100 megapascals in inches of mercury?
100 megapascals equals 29,529.98 inches of mercury.
Is a megapascal bigger than a inch of mercury?
Yes. 1 megapascal equals 295.2998 inches of mercury, so one megapascal is larger.
How to convert megapascals to inches of mercury without a calculator?
Multiply by 295.3 for a quick estimate; use a calculator for precise results.

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