The 4 Best Light Therapy Lamps of 2025

To ensure that you receive a SAD lamp’s full therapeutic benefits, there are a few important factors to consider, namely how much light a lamp delivers and how close you need to sit for the treatment to be effective.

First, you should know that the FDA does not regulate SAD lamps and other light-box devices. Experts advise using a therapeutic lamp only with a physician’s guidance, since certain medications and health conditions can be incompatible with light therapy.

Most therapeutic lamps deliver between 2,500 and 10,000 lux. A lux is a unit that measures 1 lumen per square meter. The more lux a light delivers, the less time you need to spend positioned in front of it. For most 10,000-lux lights, 30 uninterrupted minutes per day — preferably in the morning — should suffice. “If you’re going to sleep too early and want to stay awake longer, a little bit of light therapy in the afternoon can help mitigate that,” said Teodor Postolache, PhD, a professor of psychiatry at the University of Maryland School of Medicine.

We also considered how close to each box you need to sit to score the maximum results. Light intensity is subject to the inverse square law, which says that the intensity of light falls off by the square of the distance that you move away from it. For instance, if you are 2 feet away from a light source, you see a fourfold decrease in intensity. The farther away a person is able to sit from a lamp and still receive 10,000 lux for maximum efficacy, the more flexibility they have in terms of what they can be doing and how they can be sitting during treatment. “I insist, absolutely, that any reputable, reliable manufacturer has to tell the consumer what the distance it should be from the eyes to achieve 10,000 lux,” Lewy said. “If a light box doesn’t have that information, I wouldn’t use it.”

The larger the surface of the light box, the better. In his seminal book Winter Blues, Norman Rosenthal (the psychiatrist who coined the term “seasonal affective disorder”) notes that the lights “used in almost all research studies … have an illuminated surface that is at least about one foot square.” For that reason, and because many smaller therapeutic lamps have not undergone the same kind of rigorous study that their bigger cousins have received, experts recommend light boxes with the largest surfaces.

We avoided any lamps that do not have a plastic filter to remove most, if not all, ultraviolet waves (which are potentially harmful to the eye). And we avoided models that use blue LEDs, since there’s still some controversy over whether blue light (which is different from blue-enriched white light (PDF)) is harmful to the eyes.

Although many SAD lamps fit the above specifications, we discounted a number of them due to high prices, overly cumbersome designs, or dubious claims about features like “ion therapy.”

Because we are not qualified or equipped to evaluate SAD lamps for efficacy, we focused instead on how easy they are to use, how much space they require, and whether they meet their stated specs (including the total size and weight, light-face dimensions, cord lengths, and approximate light intensities). In a nonscientific test, we compared lux readings obtained with a commercial luxmeter, to check for any significant inconsistencies between stated light intensities and real-world readings.

Like any heat-producing device, light-therapy lamps should be used in an open, ventilated space (avoid putting it on a desk with a hutch, for example).

For this review, we focused on light-therapy lamps. We did not consider dawn simulators, sunrise alarm clocks, or so-called light-therapy glasses.