PEMF field claims explained: why "up to X gauss" is not a spec

What a PEMF field claim should contain

A claim you can actually use has three parts. First, the field strength, how strong the magnetic pulse is, in real units (microtesla or gauss, where 1 gauss equals 100 microtesla). Second, the frequency, how many pulses per second, in hertz. And ideally the waveform, the shape of each pulse (square, sine, sawtooth, and so on). The three only mean something together. The same field strength at 3 Hz and at 300 Hz are not the same experience, and a peak reached for a fraction of a millisecond is not the field you sit in for a session. When a brand gives you a field strength at a stated frequency, you can line it up against the next device. When it leaves either out, you can't.

The peak-gauss trick

The most common move is to lead with a peak: "up to 200 gauss," "up to 12,000 gauss." That figure is the highest point a sharp pulse touches for an instant, usually measured right at the coil. It is true in a narrow sense, and useless for deciding anything, because it says nothing about the field at a stated frequency across a session. Think of it as the same trick as a red light panel quoting its irradiance at the surface instead of where you'd sit, or a sauna quoting EMF at the heater instead of the seat. So when a device leads with a peak and gives you no sustained field at a stated frequency, RecoveryScored caps and flags its field dimension. Disclosing the waveform earns a little partial credit for being honest about the engineering, but the cap stays until there is a real spec.

The unit-less-level trick

The second move is to drop units altogether: an "intensity level" dial from 1 to 10, or a frequency you only get as a program name. There is nothing here to check, no microtesla, no gauss, no hertz. And a coverage area ("a 22-inch field") tells you how big the device is, not how strong it is. We rank a unit-less level or a missing figure at the bottom, below even a bare peak, because at least a peak is in real units.

FDA cleared vs FDA registered

Here the story mirrors red light, so it is worth a careful read. Many PEMF devices advertise "FDA registered" or "FDA-registered Class 1." That is paperwork any maker files to sell a device; it is not a finding about the device. A real FDA 510(k) clearance, for a specific use, is rare in consumer PEMF, and more common in medical bone-growth stimulators. A small number of consumer systems do hold genuine clearances, and we credit those. We flag "registered" whenever it is dressed up to read like a clearance, and we score a device that makes no FDA claim above one that dresses registration up as one.

What to actually look for

When you're looking at a device, four questions cut through it. First, is there a field strength in microtesla or gauss published with a stated frequency in hertz, not just a peak? Second, is the waveform disclosed? Third, is the FDA claim a real 510(k) clearance, or only registration? Fourth, is the price fair for its format, whether mat, coil, or wearable? Those four separate a device whose engineering you can actually read from one selling you a number with no context.

Browse the scored PEMF devices, see the verified-field-spec shortlist, or read the methodology. This is general information about specs, not medical advice, and not a claim about what PEMF does.