CONCRETE GRADES

Concrete Strength Grades (psi)

In the US, concrete is specified by f′c — the specified 28-day compressive strength, in psi, of a standard test cylinder. The grade drives the strength-based water-cement ratio and typical uses below.

Open the calculator

Choose a grade

2500 psiSidewalks (some jurisdictions), non-structural fill 3000 psiFootings, foundations, residential slabs 4000 psiDriveways, structural slabs, flatwork 5000 psiColumns, beams, heavily loaded members 6000 psiHigh-rise columns, precast/prestressed, high durability

Grades at a glance

f′c	Approx. metric	Typical uses
2500 psi	~17.2 MPa	Sidewalks (some jurisdictions), non-structural fill, very light-duty work
3000 psi	~20.7 MPa	Footings, foundation walls, non-structural slabs, general residential work
4000 psi	~27.6 MPa	Driveways, structural slabs, most commercial / structural work, exterior flatwork
5000 psi	~34.5 MPa	Columns, beams, heavily loaded members, high-durability applications
6000 psi	~41.4 MPa	High-rise columns, precast/prestressed concrete, high-durability applications

Higher strength grades need a lower water-cement ratio and usually more cement. See the method page for how w/c is selected.

Frequently asked questions

What does psi mean?

Pounds per square inch — the unit for f′c, the specified 28-day compressive strength measured on a standard cylinder.

Which grade for a driveway?

4000 psi is commonly used for driveways and exterior flatwork, but always confirm the required grade against local codes and project specifications.

2500 psiMix design and typical uses 3000 psiMix design and typical uses 4000 psiMix design and typical uses 5000 psiMix design and typical uses 6000 psiMix design and typical uses CalculatorRun a full ACI 211.1 mix design Exposure categoriesWhen durability governs over strength Prescriptive vs PerformanceThe two ways concrete is specified