Convert Concrete Strength MPa to PSI Instantly
Use this Concrete Strength MPa to PSI converter to convert compressive strength values from megapascals into pounds per square inch. It is useful for concrete mix specifications, cylinder or cube test reports, structural drawings, international project documents and comparing metric and U.S. customary strength requirements.
Convert MPa to PSI, reverse PSI to MPa, compare concrete strengths across engineering units, or use the multi-unit strength converter.
Enter concrete compressive strength in megapascals to calculate PSI and other engineering units.
Typical specified strengths are often written as values such as 20, 25, 30, 35 or 40 MPa.
Convert U.S. customary concrete strength values back to megapascals.
Enter an MPa strength to compare the same stress in PSI, ksi, kPa and Pa.
Convert between MPa, PSI, ksi, kPa and Pa using one normalized pascal-based calculation.
Concrete compressive strength is commonly reported in megapascals (MPa) in metric specifications and in pounds per square inch (PSI) in many U.S. construction documents. Both values describe stress: force divided by area. The conversion changes only the unit used to express the same stress; it does not change the physical strength of the concrete.
To convert concrete strength from MPa to PSI, multiply the MPa value by approximately 145.0377377. For everyday construction communication, this is often rounded to 145.04. For engineering documents or software calculations, keep more digits until the final result.
Example: 30 MPa × 145.0377377 = 4,351.13 PSI.
Example: 4,000 PSI × 0.0068947573 = 27.579 MPa.
These values are useful when reading international mix schedules, translating project specifications, checking test reports, or discussing strength classes with suppliers who use different unit systems.
The table below shows common compressive-strength values. The table is wrapped in a horizontal-scroll container so it remains usable on phones and narrow screens.
| MPa | PSI | ksi | kPa | Typical Reference |
|---|---|---|---|---|
| 10 MPa | 1,450.38 PSI | 1.450 ksi | 10,000 kPa | Low-strength reference |
| 15 MPa | 2,175.57 PSI | 2.176 ksi | 15,000 kPa | Light-duty reference |
| 20 MPa | 2,900.75 PSI | 2.901 ksi | 20,000 kPa | Common general reference |
| 25 MPa | 3,625.94 PSI | 3.626 ksi | 25,000 kPa | General structural reference |
| 30 MPa | 4,351.13 PSI | 4.351 ksi | 30,000 kPa | Common structural value |
| 35 MPa | 5,076.32 PSI | 5.076 ksi | 35,000 kPa | Higher specified strength |
| 40 MPa | 5,801.51 PSI | 5.802 ksi | 40,000 kPa | Higher structural value |
| 45 MPa | 6,526.70 PSI | 6.527 ksi | 45,000 kPa | Higher-performance reference |
| 50 MPa | 7,251.89 PSI | 7.252 ksi | 50,000 kPa | High-strength range reference |
| 55 MPa | 7,977.08 PSI | 7.977 ksi | 55,000 kPa | ≈ 8,000 PSI |
| 60 MPa | 8,702.26 PSI | 8.702 ksi | 60,000 kPa | High-strength reference |
| 70 MPa | 10,152.64 PSI | 10.153 ksi | 70,000 kPa | Advanced structural use |
| 80 MPa | 11,603.02 PSI | 11.603 ksi | 80,000 kPa | High-performance reference |
| 100 MPa | 14,503.77 PSI | 14.504 ksi | 100,000 kPa | Very high strength reference |
25 × 145.0377377 = 3,625.94 PSI.
30 × 145.0377377 = 4,351.13 PSI.
35 × 145.0377377 = 5,076.32 PSI.
40 × 145.0377377 = 5,801.51 PSI.
The same method works for decimal strengths. A test result of 32.4 MPa is approximately 4,699.22 PSI. Keeping a few decimal places can be useful when transferring laboratory results, while project drawings may intentionally round to a specified nominal strength.
A megapascal is one million pascals. A pascal is one newton of force acting over one square meter. In concrete work, MPa is commonly used to express compressive strength because typical structural concrete strengths fall conveniently in the tens of megapascals rather than millions of pascals.
When a specification calls for 30 MPa concrete, it is describing a specified compressive stress value. The actual acceptance, sampling, curing, testing age and statistical requirements depend on the governing project specification and code. A unit converter cannot determine whether a test passes or fails a contract requirement; it only converts the reported stress value.
PSI means pounds-force per square inch. A concrete strength of 4,000 PSI means the reported compressive stress is 4,000 pounds-force per square inch. This is not the same as saying a concrete element can simply carry 4,000 pounds on every square inch in service. Structural design includes geometry, load combinations, reinforcement, safety factors and code provisions.
For quick comparison, 4,000 PSI is approximately 27.58 MPa, 5,000 PSI is approximately 34.47 MPa, and 6,000 PSI is approximately 41.37 MPa.
International projects often combine drawings, material data sheets, testing equipment and supplier documentation from different countries. Metric documents may specify 25, 30 or 40 MPa, while U.S. documents may use 3,000, 4,000 or 5,000 PSI. Converting between MPa and PSI allows engineers, estimators, inspectors, contractors and concrete suppliers to compare the same strength requirement without changing the underlying material property.
Concrete compressive strength is frequently discussed at 28 days, but test ages can vary by specification, mix design, curing regime and project purpose. If a laboratory report gives a 28-day cylinder result of 33 MPa, converting the unit gives about 4,786 PSI. The conversion does not alter the test age or test method.
When comparing results, confirm that both values refer to the same specimen type, age and test standard. Cylinder and cube results should not be treated as interchangeable merely because both can be converted between MPa and PSI.
MPa-to-PSI conversion is a pure unit conversion. It is not a cube-to-cylinder strength conversion. Different specimen geometries can produce different measured compressive strengths, and the relationship depends on factors such as specimen size, concrete strength and testing procedures. If a report says 40 MPa cube strength, converting that value to PSI only gives the same cube-test stress in another unit.
Do not apply a universal percentage to convert cube strength to cylinder strength unless the governing standard, engineer or project specification provides an accepted relationship for that context.
Those factors apply within pascal-based metric units, not MPa to PSI. Use about 145.0377.
1 ksi = 1,000 PSI. A 5,000 PSI concrete strength is 5 ksi, not 5,000 ksi.
30 MPa is about 4,351 PSI, not exactly 4,000 or 4,500 PSI.
Unit conversion does not convert cube-test strength into cylinder-test strength.
Continue with related calculators such as MPa to PSI, PSI to MPa, kPa to PSI, MPa to kPa, Concrete Calculator, Concrete Slab Calculator and Concrete Bags to Cubic Yards. These tools help move from strength specifications to volume and material planning while keeping each calculation separate.
For unit-conversion guidance, see the NIST Guide to SI conversion factors. For concrete strength acceptance and code-related information, consult the American Concrete Institute strength-test FAQ and the standards specified for your project. These references are more appropriate for engineering decisions than relying on a general-purpose converter alone.
The same compressive stress can be written in metric MPa or U.S. PSI units.
Quick answers for concrete compressive-strength conversion.