Magnet Specs:

 

Dimensions: 1/2" dia. x 1/8" thick

Tolerances: ±0.004" x ±0.004"

Material: NdFeB, Grade N42

Plating/Coating: Ni-Cu-Ni (Nickel)

Magnetization Direction: Axial (Poles on Flat Ends)

Weight: 0.106 oz. (3.02 g)

Pull Force, Case 1: 6.44 lbs

Pull Force, Case 2: 16.00 lbs

Surface Field: 2952 Gauss

Max Operating Temp: 176ºF (80ºC)

Brmax: 13,200 Gauss

BHmax: 42 MGOe

 

The surface Field Gauss is 2952. 

The magnetic strip on credit cards comes in two varieties.  The high-coercivity ones, like a typical credit card, require a field strength of somewhere around 4,000 gauss to demagnetize.  The low-coercivity ones that are often re-written, like hotel keys or gift cards, require about 300 gauss.

A D82 magnet has a listed surface field less than 3,000 gauss.  Will this magnet be OK at any distance?

No, not necessarily.  While thinner magnet shapes exhibit weaker magnetic fields, the magnetic fields are usually stronger out at the edges.  The listed surface field of 2,952 gauss is true only at the very center of the magnet.  For a magnet this size, we find that the magnetic field exceeds 4,000 gauss out at the edges of the magnet, within about 0.02” from the surface from the magnet.  Our testing confirmed this:

After rubbing the magnet 0.03” away from the magnetic stripe, the card still worked great every time.

After rubbing the magnet 0.02” away from the magnetic stripe, the card didn’t work at all.

Our wallets keep the magnetic strip 0.5” away from the magnet. This keeps your card strips well away from the danger zone.  Also the magnet is off to the side 0.5” and the strip is never directly on top of the magnet.   However we do not recommend using the money clip to store the credit cards because the Gauss between the two magnets comes close to 4000.  The logo on the top of the clip has a thickness of 0.13” for protection.  Using the wallet as designed will not demagnetize your cards.