How to Choose a Red Light Therapy Panel: What the Numbers Mean

Panels are sold on numbers: watts, wavelengths, LED counts, irradiance. Some of those numbers decide what the panel does to your skin, some are marketing, and one of them is routinely quoted without the detail that gives it meaning. Here is how to read a panel listing, in the order the numbers actually matter.

1. Irradiance, stated at a distance

Irradiance is how much light lands on the skin, given in mW/cm² or W/m². Together with time, it is what decides the dose, and it is the figure most listings get wrong. Check two things: that a figure is given at all, and that it says at what distance it was measured. Light falls away quickly as you move back, so a number like 200 mW/cm² means nothing without a distance beside it. A panel that publishes irradiance at a stated distance is telling you something you can use. A panel that publishes only watts is telling you its electricity bill.

Kivorla's panel is specified at six inches: at least 1567 W/m² across the full spectrum, of which at least 1200 W/m² is near-infrared and at least 150 W/m² is red.

2. Which wavelengths, and whether you can control them

Most panels offer two: one red around 660 nm and one near-infrared around 850 nm, wired together so both are always on. That covers the two most studied bands and nothing else. More wavelengths are only useful if you can choose between them, because red, near-infrared, amber and blue do different things at different depths, and a session for the face is not a session for a hamstring.

Kivorla's panel carries nine, from 480 to 1060 nm, and each one can be dimmed from 1 to 100% on its own. If you want one panel to do more than one job, that is the feature to look for: not the count, the control.

3. Size and coverage

A panel treats what it faces. A small panel treats a face or a knee. A 640 mm panel treats the torso and thighs from one position, or the whole back. Buy for the largest area you plan to treat, because moving a panel around the body every session is how routines die. Note the weight as well: Kivorla's is 6.3 kg and hangs from its hook and pulley, so it needs a door or a wall, not a shelf.

4. Timer and controls

A timer is not optional. Dose is irradiance multiplied by time, and a panel without a timer leaves you counting minutes on your phone. Look for a range that covers the ten to twenty minute sessions the published studies used, and for a control you will actually reach from where you sit: a touchscreen on the unit, a remote, or an app. Kivorla's runs from 1 to 30 minutes, defaults to 15, and takes all three.

5. Lens angle

The LEDs on a panel sit behind lenses that set how widely the light spreads. A narrow lens, around 30 degrees, throws light further and suits use from a distance. A wide lens, around 90 degrees, spreads it evenly and suits use up close. Most panels fix one angle and do not tell you which. Kivorla's is offered in 30, 60 or 90 degree lenses. A listing that mentions the angle at all is a sign the maker understands the trade-off.

What to ignore

• Watts on their own. Rated power tells you what the panel draws from the wall, not what reaches your skin.
• LED count on its own. What matters is irradiance at the skin, which depends on the chips, the lenses and the distance, not the number in the listing.
• The words medical grade. They are not a regulated term for these devices.
• Any panel that will not state irradiance at a distance.

Eyes, every time

Most of a panel's output is invisible near-infrared. Goggles should be in the box, and on your face before the panel comes on. We explain why in Is red light therapy safe for your eyes?

Kivorla devices are general wellness devices, not medical devices. Individual results vary. Read the precautions supplied with your device before first use, and speak to a qualified healthcare professional if you are unsure whether a device suits you.