How long should a red light therapy session be?
Dose equals irradiance times seconds. Pick a panel, a distance and a target dose and the tool returns the minutes — and names which panels in the catalog reach that dose inside ten minutes.
Independent and reader-supported. We earn a commission if you buy through our links, at no extra cost to you. Rankings are never sold, and every figure says where it came from. Prices verified September 2, 2026.Full disclosure
Short answer
Every panel in our catalog at this distance
The minutes column is the product link on this page: a panel that cannot reach your dose inside a sensible session is the wrong panel, whatever its LED count. Panels whose maker publishes no per-model irradiance figure show no minutes, because we are not going to invent one.
| Panel | Published at 6 in | At your distance | Minutes to your dose | Inside ten minutes |
|---|---|---|---|---|
| Mito Red Light MitoPRO 750X | 70 mW/cm² manufacturer figure, spectroradiometer | 70 mW/cm² | 7.1 min | yes |
| Mito Red Light MitoPRO 1500X | 73 mW/cm² manufacturer figure, spectroradiometer | 73 mW/cm² | 6.8 min | yes |
| Mito Red Light MitoPRO 300X | 56 mW/cm² manufacturer figure, spectroradiometer | 56 mW/cm² | 8.9 min | yes |
| Hooga PRO1500 | 189 mW/cm² manufacturer figure, instrument not named | 189 mW/cm² | 2.6 min | yes |
| Hooga ULTRA750 | 161 mW/cm² manufacturer figure, instrument not named | 161 mW/cm² | 3.1 min | yes |
| Hooga HG300 | 73 mW/cm² manufacturer figure, instrument not named | 73 mW/cm² | 6.8 min | yes |
Three worked examples
All three on the Mito PRO 750X, at the greater than 70 mW/cm² Mito Red publishes for it at six inches on a spectroradiometer.
| Target | Irradiance there | Minutes | Ten minutes would give |
|---|---|---|---|
| Skin, 15 J/cm² at 6 in | 70 mW/cm² | 3.6 min | 42 J/cm² from a flat 10-minute session |
| Knee joint, 30 J/cm² at 6 in | 70 mW/cm² | 7.1 min | 42 J/cm² from a flat 10-minute session |
| Knee joint, 30 J/cm² at 12 in | 17.5 mW/cm² | 28.6 min | 10.5 J/cm² from a flat 10-minute session |
How the math works
time (s) = dose × 1000 ÷ irradiance
E(d) = E(6 in) × (6 ÷ d)²
The first two lines are exact. The third is an approximation, and it is the one worth understanding: a panel is not a point source. Inverse-square falloff describes light from a point, and close to a large flat array the real falloff is gentler than that. So the minutes this tool reports at six inches are conservative, and the minutes at eighteen inches are roughly right. Six inches is the standard measurement distance, which is why it is the anchor.
The number everything multiplies
Every irradiance figure here is manufacturer-published. Mito Red states a spectroradiometer reading at six inches for each of its panels and names the instrument, which is the only reason those panels can be computed at all. Hooga publishes no per-model figure, so its rows return no minutes.
This matters more than it sounds. Consumer solar meters — the $30 devices most brands and most reviewers use — substantially over-read narrow-band red and near-infrared. Mito Red publishes both readings for the same panel at the same distance: over 160 mW/cm² on a consumer meter against over 70 mW/cm² on a spectroradiometer. If you dose against the inflated figure you will believe ten minutes gave you 96 J/cm² when it gave you about 42. Cross-brand comparison is meaningless unless you know the instrument.
We have not put a spectroradiometer on any panel. That run, at six and twelve inches, is the single most valuable measurement available to this site, and the day it exists this tool switches to measured values and becomes the only one of its kind. Until then it is arithmetic on numbers other people published, and the table above says whose.
Dose bands by use case
Our reading of published protocol ranges, reproduced from our dosing guide. Not a bench result, and not a clinical recommendation.
| Use case | Dose J/cm² per session | Sessions per week |
|---|---|---|
| Skin, face and superficial tissue | 10–20 | 3–5, daily in some trials |
| Joints and deep tissue (knee, shoulder, low back) | 30–60 | 3–5 |
| Large muscle groups after training | 30–40 | 3–4 |
| Maintenance once you have a routine | 20–40 | 2–3 |
Before you use one
This tool computes an energy dose. It makes no claim about what that dose does. Red and near-infrared light contains no UV and is not a burn risk at home-panel irradiance, but there are situations where the sensible answer is to ask a clinician first: if you are pregnant, if you take a photosensitising medication, if you have a condition affecting the eyes or skin, or if you are treating an area with an active skin cancer or an undiagnosed lesion. Do not stare into the panel — near-infrared is invisible and your blink reflex will not protect you. Nothing on this page is medical advice.
What the output points at
Prices verified September 2026 from manufacturer and retailer pages. This category discounts constantly, so check before you buy.
Mito Red Light MitoPRO 750X
The default full-featured panel for targeted recovery work
The panel we would buy with our own money. Six wavelengths, an honest published gap between spectroradiometer and consumer-meter numbers, and a 3-year warranty.
- LEDs
- 150 red / 300 NIR
- Wavelengths
- 590, 630, 660, 810, 830, 850 nm
- Irradiance @6″
- >70 mW/cm² spectroradiometer; >160 consumer meter
- Dimensions
- 10" x 23"
- Power
- 225W
- Warranty
- 3 years
What we liked
- Publishes both spectroradiometer and consumer-meter irradiance — almost nobody does
- Six wavelengths including 590nm and the 810/830 deep-tissue band
- 3-year warranty at a mid-market price
What we did not
- 10" x 23" covers a torso, not a full body — you will reposition
- 225W draw means real heat off the back of the panel
- Stand and door-hang hardware are extra
Mito Red Light MitoPRO 1500X
Back, posterior chain and full-torso protocols
Torso-to-thigh coverage in one pass. If you are treating your back or legs rather than a joint, the 43-inch panel is the one that ends the repositioning.
- LEDs
- 300 red / 600 NIR
- Wavelengths
- 590, 630, 660, 810, 830, 850 nm
- Irradiance @6″
- >73 mW/cm² spectroradiometer; >160 consumer meter
- Dimensions
- 10" x 43"
- Power
- 445W
- Warranty
- 3 years
What we liked
- 43" tall covers shoulders to thighs standing
- Same six-wavelength spectrum as the 750X
- Marginally higher measured irradiance than the smaller panel
What we did not
- 445W and 43 inches — this needs a wall or a serious stand
- $1,299 is real money for a single-purpose device
- Still not full-body without two panels
Mito Red Light MitoPRO 300X
Targeted joint work, faces, and testing whether you will stick with it
The entry point into six-wavelength light without dropping to single-chip budget panels. Right size for a knee, shoulder or face.
- LEDs
- 60 red / 120 NIR
- Wavelengths
- 590, 630, 660, 810, 830, 850 nm
- Irradiance @6″
- >56 mW/cm² spectroradiometer; >130 consumer meter
- Dimensions
- 9.5" x 14.5"
- Power
- 125W
- Warranty
- 3 years
What we liked
- Full six-wavelength spectrum at under $500
- Small enough to sit on a desk or nightstand
- 125W draw runs cool and quiet
What we did not
- Lowest measured irradiance in the X line
- 9.5" x 14.5" is a single-joint device
- You will want the bigger one within a year
What we have not measured
The arithmetic on this page is standard. The figures going into it come from the people selling the equipment: Panel irradiance at 6 in and 12 in on a spectroradiometer, for every panel in the catalog rather than the three whose maker publishes one.
- Every irradiance figure driving this tool is manufacturer-published. Mito Red states a spectroradiometer reading at six inches for each of its panels and names the instrument, which is why those three are the only ones the tool can compute. Hooga does not publish a per-model figure, so its panels return no minutes rather than a guess.
- We have not put a spectroradiometer on any panel. That run, at six and twelve inches, is the single most valuable measurement available to this site, and the tool switches to measured values the day it exists.
- The dose equation is exact and the inverse-square falloff is physics, but a panel is not a point source. Close to a large panel the falloff is gentler than inverse-square, so the minutes at six inches are conservative and the minutes at eighteen inches are roughly right.
- Irradiance is quoted at the centre of the panel, which is always its highest reading. Corners can be substantially lower, and no brand publishes a uniformity map.
- The dose bands by use case are our reading of published protocol ranges, not a bench result and not a clinical recommendation.
Our testing method says the same about every figure on the site, and lists which bench runs are still owed.
Questions buyers actually ask
Is 10 minutes of red light therapy enough?
At six inches from a panel genuinely delivering 70 mW/cm² on a spectroradiometer, ten minutes is 42 J/cm², comfortably inside the 10 to 60 J/cm² band most published protocols target. At twelve inches the same ten minutes delivers about 11 J/cm², the bottom of the band. Distance decides whether ten minutes is enough, and it is the variable most people set by accident.
How do you calculate red light therapy dose?
Dose in J/cm² equals irradiance in mW/cm² multiplied by time in seconds, divided by 1000. The arithmetic is trivial; getting a trustworthy irradiance number to put into it is the hard part. Consumer solar meters substantially over-read narrow-band red and near-infrared, so a panel advertising 160 mW/cm² on a solar meter may be delivering about 70 on the instrument that counts.
How far should I sit from a red light panel?
Six inches is the standard measurement distance and a sensible session distance for targeted work. Irradiance falls off roughly with the square of distance, so twelve inches gives you about a quarter of the six-inch figure and needs roughly four times the time for the same dose. Sitting across the room from a panel while you work is not a protocol.
Can you overdo red light therapy?
The literature describes a biphasic dose response, meaning that past a point more energy produces less effect rather than more. It is not a burn risk at home-panel irradiance. Practically, stay inside the 10 to 60 J/cm² band and do not add time to a session that already reaches it. Do not stare into the panel; near-infrared is invisible and your blink reflex will not protect you.
The guides this tool belongs to
A calculator answers one question with a number. These answer the ones around it.
Prices captured September 2026 from manufacturer and retailer pages and subject to frequent promotion. Nothing on this page is medical, electrical or financial advice — sauna and plunge circuits are licensed work in every US jurisdiction.