Light
Red light therapy panels, with the dosing arithmetic nobody prints on the box
Panels, wavelengths and the dose maths every brand skips — including why the irradiance figure on the box is usually not the one reaching your skin.
Red light is the fastest-growing corner of home recovery, and the one with the widest gap between marketing and measurement. US search demand for red light panels has grown roughly thirty-fold in three years. The number of brands publishing a defensible irradiance figure has not grown at all.
Here is the arithmetic that makes the category legible. Dose in joules per square centimetre equals irradiance in milliwatts per square centimetre times seconds, divided by one thousand. Most published protocols land between 10 and 60 J/cm². So a panel genuinely delivering 70 mW/cm² at six inches gives you about 42 J/cm² in ten minutes — right in the band. The same panel at twelve inches delivers roughly a quarter of that, because irradiance falls off fast with distance.
Which is why the single most useful question to ask a red light brand is not "how many watts" but "measured with what, at what distance". A consumer solar meter — the $30 device most brands and most reviewers use — substantially over-reads narrow-band red and near-infrared. When a brand publishes both a meter number and a spectroradiometer number, the honest one is the smaller one.
The decisions this section settles
- Is the irradiance number real?
- Usually not, as stated. Most brands quote consumer solar-meter readings, which over-read red and near-infrared LEDs substantially. Mito publishes both meter and spectroradiometer figures, and the gap is roughly 2×.
- How big a panel?
- Panel size sets session length, not effectiveness. A 10 x 14 inch panel treats a knee; treating a back with it means four repositions. Buy the size that matches the body area you actually care about.
- Which wavelengths?
- 660nm for skin and superficial tissue, 810–850nm for deeper penetration. Extra wavelengths like 590nm and 830nm are plausible additions, not proven necessities.
- How long per session?
- Dose is irradiance times time. At a genuine 70 mW/cm² at six inches, ten minutes delivers about 42 J/cm² — inside the commonly cited 10–60 J/cm² band. Double the distance and you need roughly four times the time.
- Single, dual or quad chip?
- More chips per LED package means more optical power per unit area, which is why quad-chip panels cost more and run hotter. It is the clearest spec-to-price relationship in the category.
- Is any of this FDA cleared?
- Several devices carry Class II clearances for specific indications like temporary pain relief. That is not the same as proof of the broader claims made in marketing copy.
Guides in this section
Buying guide
The best red light therapy panels of 2026, judged on measured irradiance
Most red light brands quote solar-meter irradiance figures that over-read by roughly 2x. We ranked the market on the numbers that survive a spectroradiometer — and on which brands are honest enough to publish both.
Protocol guide
Red light therapy dosing: the distance and time table nobody prints
Dose equals irradiance times seconds. Get the irradiance figure wrong and every session is wrong. Here is the arithmetic, the distance falloff, and why brand-published numbers usually overstate by about 2x.
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