Is N52 always stronger than N35?

For the same geometry, magnetization, magnetic circuit, temperature, and supplier specification, N52 generally offers higher magnetic output. It does not guarantee that any N52 finished product will hold more than a differently sized or better-designed N35 product.

Does the N number equal pull force?

No. The N number relates to the material's maximum energy product. Finished-product pull force depends on geometry, contact area, air gap, target steel, assembly design, magnetization, temperature, and the test method.

What do M, H, SH, UH, EH, and AH mean after a grade?

They identify families with increased intrinsic coercivity and temperature capability. Exact property limits and allowable service temperature are manufacturer- and design-specific, so the suffix must be checked against the approved material specification and demagnetization curve.

Neodymium Magnet Grades: N25 to N52 Explained

N25, N30, N35, N42, and N52 are not five application categories. They are selected points within a broader family of sintered neodymium-iron-boron material grades. The grade should be chosen from engineering requirements, not labels such as “office,” “kitchen,” or “tools.”

What the N number means

The number following N is associated with the material’s maximum energy product, written as (BH)max and commonly expressed in megagauss-oersteds (MGOe). For example, a supplier’s N42 grade is designed around a higher energy-product range than its N35 grade.

(BH)max describes how much magnetic energy a material can deliver under defined conditions. It is a material property derived from the demagnetization curve. It is not:

a pull force in pounds or kilograms;
a safe load rating;
a surface-gauss value;
a universal promise that applies across every manufacturer;
a substitute for the complete material specification.

Manufacturer data sheets also state residual flux density Br, normal coercivity HcB, intrinsic coercivity HcJ, temperature coefficients, and recommended operating limits. Those values matter when the magnet operates near heat, opposing fields, a large air gap, or a difficult load line.

How selected grades compare

The following table is a selection guide, not a complete grade list or guaranteed FINDMAG stock program.

Selected grade	What the designation indicates	Appropriate interpretation
N25	Lower maximum energy product within the broad NdFeB family	May suit cost-sensitive or less space-constrained designs when its full specification is adequate
N30	Higher energy product than N25 within a comparable grade family	A material option to evaluate against size, temperature, coercivity, and supply requirements
N35	Widely specified general-purpose energy level	Often a practical baseline for design comparisons, subject to the complete data sheet
N42	Higher energy product than N35	Can support more compact geometry or higher output when the magnetic circuit can use it
N52	Near the upper end of common room-temperature N-grade offerings	Useful where compact high output is important, but not automatically the best thermal or commercial choice

Many other grades exist between or beyond these selected labels. Availability, guaranteed property ranges, and suffix systems vary by producer. A buyer should therefore request the actual material data sheet and delivery specification instead of treating the N number as the whole specification.

Does a higher grade create more holding force?

If two magnets have the same dimensions, shape, magnetization direction, coating, temperature, target steel, air gap, and magnetic circuit, the higher grade generally has the potential to deliver higher magnetic output.

Real products rarely keep every variable identical. Finished holding force can change substantially with:

diameter, thickness, pole area, and shape;
axial, diametric, radial, or multipole magnetization;
an open magnet versus a steel cup or return-path assembly;
the target steel’s material, thickness, area, and surface condition;
paint, adhesive, plating, plastic, or any other air gap;
operating temperature and exposure time;
manufacturing tolerances and assembly position;
direct pull, shear, or peel loading;
the test fixture and acceptance method.

A larger N35 magnet or a well-designed N35 pot-magnet assembly can outperform a smaller bare N52 magnet in a specific test. Grade is one design input, not the finished-product rating.

Why N52 is not always the best choice

Choosing the highest available N number can add cost without solving the real constraint. The magnetic circuit may already be limited by steel saturation, available pole area, air gap, or geometry. A high-energy grade may also provide less coercivity or temperature margin than a suffix grade selected for the operating environment.

A B2B selection should balance:

Required output at the use temperature
Resistance to irreversible demagnetization
Available volume and geometry
Air gap and mating magnetic circuit
Corrosion protection and coating
Dimensional and magnetic tolerances
Cost, availability, MOQ, and lead time
Required inspection and traceability

The goal is not the largest grade number. It is the lowest-risk material and geometry that meet the verified product requirement.

What the temperature suffix means

Grade families may add suffixes such as M, H, SH, UH, EH, or AH. These generally indicate progressively higher intrinsic-coercivity families designed for greater resistance to demagnetization at elevated temperature.

Do not convert a suffix into a universal maximum operating temperature without the supplier’s data. Allowable service temperature depends on the manufacturer’s guaranteed properties, magnet shape, permeance coefficient, opposing field, thermal cycle, and the acceptance limit for irreversible loss.

For a heated application, request:

the full grade and supplier specification;
Br, HcB, HcJ, and (BH)max ranges;
demagnetization curves at relevant temperatures;
temperature coefficients;
magnet geometry and operating load line;
irreversible-loss acceptance criteria;
validation after the intended thermal cycle.

A better way to specify grade in an RFQ

“N52 magnet” is not enough for a controlled quotation. A useful RFQ identifies:

material family and proposed grade or required magnetic performance;
drawing, dimensions, tolerances, edge requirements, and magnetization direction;
coating and corrosion environment;
operating and storage temperature range;
mating steel or magnetic-circuit geometry;
target surface field, flux, magnetic moment, pull force, or system output—and its test method;
inspection method, sampling plan, documentation, and traceability;
annual quantity, order quantity, packaging, and target date.

When the required grade is uncertain, provide the application and system constraints. Engineering review can compare N35, N42, N52, or a higher-coercivity suffix family without assuming that the highest grade is automatically the best value.

Send your magnetic requirement to FINDMAG or explore the Neodymium Magnets category.

Technical references

The listed sources show representative property tables and terminology. Final purchasing requirements should use the approved supplier specification for the selected material and part geometry.

Magnetic Materials & Forms

Magnetic Products by Use