Convert Pressure from kilopound per square inch to megapascals (ksi to MPa)

Kilopound per Square Inch to Megapascal Conversion Formula

To convert a stress from kilopounds per square inch (ksi) to megapascals (MPa), multiply by 6.8948.

• MPa = ksi × 6.8948

One ksi is 1,000 psi, and one psi is 6,894.76 Pa, so one ksi is 6.89476 MPa exactly (to six figures). A rougher but memorable anchor: 1 ksi ≈ 7 MPa, good to within 1.5% for quick checks.

Step-by-Step Example

A US material certificate lists a bolt's minimum tensile strength as 120 ksi, and a European design calculation needs it in MPa:

1. Take the stress: 120 ksi
2. Multiply by 6.8948: 120 × 6.8948 = 827.4 MPa

At 827 MPa, the bolt slots neatly into the metric property class 8.8 territory (nominal 800 MPa) — the two specifications are describing near-identical steel.

Quick Reference Table

The Transatlantic Materials Dictionary

Ksi-to-MPa is the everyday translation of materials engineering, because the world's two dominant specification systems price strength in different currencies: ASTM and SAE standards quote yield and tensile strengths in ksi (A36 steel yields at 36 ksi, aerospace 4340 tempers to 150–260 ksi), while EN, ISO and JIS standards — and every scientific paper — use MPa (S355 yields at 355 MPa, the same 4340 range reads 1,034–1,793 MPa). Any project mixing American materials with metric design codes, or vice versa, performs this multiplication constantly: qualifying a substitute alloy, checking an imported fastener against Eurocode capacity formulas, or reconciling a US mill certificate with a metric FEA model. Fatigue and fracture work adds a wrinkle — stress-intensity factors convert as ksi·√in × 1.0989 = MPa·√m, a different factor that is routinely misapplied as 6.89. The saving habit is the sanity anchor: ordinary structural steels live at 36–50 ksi and 250–350 MPa. A conversion that lands a mild steel at 2,400 MPa (or 5 ksi) has slipped a unit, and the anchor catches it before the calculation propagates.

How many kilopound per square inch are in one megapascal? One megapascal (MPa) contains 0.14503768078 kilopound per square inch (ksi) — the inverse of the factor above. Multiplying by 6.8947600004501395751 takes you from kilopound per square inch to megapascals; multiplying by 0.14503768078 brings you back.

Put in words: one kilopound per square inch equals 6.8947600004501395751 megapascals, so the kilopound per square inch is the larger unit of this pair. Converting between them never changes the amount of pressure being measured — only the size of the unit you count it in.

What is a kilopound per square inch (ksi)?

A kilopound per square inch (ksi) is a unit of pressure and stress used in the Imperial and US customary systems of measurement.

It represents a force of one thousand pounds-force applied to an area of one square inch.

How to Convert ksi to psi and MPa

A kilopound per square inch (ksi) is a scaled unit directly related to the more common pound per square inch (psi). The prefix "kilo-" signifies one thousand.

Here are the most common conversions:

• ksi to psi: 1 ksi = 1,000 psi
• ksi to MPa: 1 ksi ≈ 6.895 megapascals (MPa)

The conversion to megapascals (MPa) is essential for converting measurements to the SI (metric) system.

The Role of ksi in Measuring Material Strength

In materials science and structural engineering, ksi is a primary unit for quantifying the mechanical properties and material strength of a substance.

It is commonly used to express:

• Ultimate Tensile Strength (UTS): The maximum stress a material can handle before it breaks (fractures).
• Yield Strength: The stress at which a material will begin to bend (deform) permanently.

For example, the strength of high-performance materials like structural steel and aluminum alloys is frequently specified in ksi.

This provides engineers with the critical data needed for safe and reliable design.

While the metric system's megapascal (MPa) is the international standard, ksi remains prevalent in American engineering, particularly in the aerospace, automotive, and construction industries.

What is a megapascal (MPa)?

If you've ever looked at engineering specifications, construction materials, or high-pressure equipment, you've likely seen the term 'MPa.'

A megapascal (MPa) is a unit of pressure in the metric system, equal to one thousand kilopascals (1000 kPa).

The plural form is megapascals.

Using MPa to Measure Material Strength

The megapascal (MPa) is a fundamental unit for quantifying the strength of materials in engineering and construction.

It is commonly used to express a material's ultimate tensile strength (the maximum stress it can withstand while being pulled apart) and compressive strength (its resistance to being squeezed).

For example, structural steel might have a tensile strength of 400 MPa. In comparison, high-performance concrete can have a compressive strength exceeding 80 MPa.

MPa to PSI and Bar Conversions (and kPa)

Understanding how to convert megapascals to other pressure units is crucial for global applications.

Here are the most common conversions:

• 1 MPa = 1,000 kilopascals (kPa)
• 1 MPa = 145.04 pounds per square inch (PSI)
• 1 MPa = 10 bar

The pound per square inch (PSI) is a unit commonly used in the United States for measuring tire pressure and hydraulic systems.

The bar is a unit often used in Europe for weather forecasting and scuba diving.

Real-World Examples of Megapascal Pressures

Megapascals are used to describe immense pressures found in both natural and industrial settings.

The water pressure at the bottom of the Mariana Trench, the deepest point in the ocean, is about 108.6 MPa.

In industry, a high-pressure waterjet cutter operates at pressures ranging from 200 to 600 MPa, demonstrating enough force to slice through metal and stone.

kilopound per square inch to megapascal Conversion Table

Here are some quick reference conversions from kilopound per square inch (ksi) to megapascal (MPa):

This conversion in other languages

Engineering datasheets across Europe write kilopound per square inch to megapascal several different ways. The calculation is the same in every one of them.