Far Infrared vs Near Infrared: How Deep Each Goes and What It Does
Far infrared vs near infrared comes down to where the energy lands: near infrared (780 to 1,400 nm) passes several millimetres into tissue, while far infrared (3,000 nm to 1 mm) is absorbed in roughly the top tenth of a millimetre of skin and is felt mainly as heat. Red light panels and masks pair near-infrared with red light, while most infrared saunas run on far infrared heaters. Below: the bands, depth, how each works, the sauna, textile and LED studies, safety, and where Kivorla devices fit.
Key takeaways
- International guidelines place near-infrared (IR-A) at 780 to 1,400 nm and far infrared (IR-C) at 3,000 nm to 1 mm. ICNIRP, 2013
- Far infrared has a penetration depth of about 0.1 mm or less in skin, while near-infrared penetrates several millimetres. ICNIRP, 2006
- In a laboratory test on the cheek, 830 nm near-infrared came through at 4.0 mW/cm² against 1.4 mW/cm² for 633 nm red light. Jagdeo, 2012
- In a sham-controlled trial of 76 people, 830 nm, 633 nm or both on the skin twice a week for 4 weeks reduced wrinkles by up to 36% from baseline. Lee, 2007
- A 2009 review of far infrared sauna studies found "limited moderate evidence" for lowering blood pressure and for heart failure. Beever, 2009
Far infrared vs near infrared: what is the difference?
They sit at opposite ends of the invisible infrared range: near infrared starts just past visible red light, and far infrared covers much longer waves. Near-infrared passes into tissue as light, while far infrared is absorbed at the skin surface and felt as warmth.
| Band | Wavelength | How far it reaches into skin | Common sources |
|---|---|---|---|
| Red (visible) | About 620 to 700 nm | Roughly 2 to 3 mm | LED panels and masks |
| Near-infrared (IR-A) | 780 to 1,400 nm | Several millimetres | LED panels and masks, sunlight, filtered infrared lamps |
| Mid-infrared (IR-B) | 1,400 to 3,000 nm | Under 1 mm | Some filtered lamps |
| Far infrared (IR-C) | 3,000 nm to 1 mm | About 0.1 mm or less | Sauna wall and rod heaters, warm surfaces, the human body |
Bands and depths come from the International Commission on Non-Ionizing Radiation Protection (ICNIRP). ICNIRP, 2006 Our red light therapy wavelength chart shows depth across the red and near-infrared range.
Labels vary because standards vary. ISO 20473 calls 0.78 to 3.0 microns near infrared, 3 to 50 microns mid infrared and 50 to 1,000 microns far infrared. Tsai and Hamblin, 2017 Under that scheme, the 3 to 50 micron heat that saunas give off would be called mid infrared.
One micron is 1,000 nm. The body itself radiates at about 10 microns, so "3 to 14 microns" on a label describes heat.
Does far infrared go deeper into the body than near infrared?
No: ICNIRP describes far infrared as "totally absorbed in the stratum corneum and superficial epidermis", the outermost layers of skin. ICNIRP, 2006
By about 0.25 mm, 95% of incoming far infrared has been absorbed. The same statement explains that "deep heating by IR-C is only achieved by heat transfer": warmth travels inward by conduction and blood flow. Some sources claim far infrared reaches several centimetres, but measurements put its absorption in the outer skin.
Near-infrared behaves differently. In a small laboratory study, researchers shone 830 nm and 633 nm LED light through tissue and measured what came out. Jagdeo, 2012
- Cheek, light pressure: 4.0 mW/cm² of 830 nm came through, against 1.4 mW/cm² of 633 nm.
- Through an intact head specimen at the temple: 0.30 mW/cm² of 830 nm, against under 0.001 mW/cm² of red.
The study was small, but it shows near-infrared carrying further through tissue than red.
Why does a far infrared sauna feel hot while near-infrared light feels mild?
Far infrared puts all its energy into the outermost skin, where warmth is sensed, so skin temperature rises more than with near or mid infrared. Near-infrared spreads its energy through several millimetres, so the same power feels gentler.
ICNIRP notes that far infrared is "completely absorbed in the most superficial layers of the skin". ICNIRP, warming cabins Its guidance on infrared cabins also shows that the heater type decides the band:
- Wall and rod heaters: give off almost solely far infrared.
- Filtered lamps: give off near or mid infrared plus a little visible light. This is what "near infrared sauna" usually means.
- Air temperature: around 40°C in infrared cabins, against 85 to 90°C in traditional saunas.
Cleveland Clinic gives 43 to 57°C for infrared saunas and 66 to 91°C for traditional ones. Cleveland Clinic, 2026
Some warmth close to an LED panel is normal, but warmth is not how light therapy works. Our infrared vs red light therapy guide covers this in more detail.
How do near infrared and far infrared work in the body?
Near-infrared is thought to act mainly as light absorbed inside cells, a process called photobiomodulation. Far infrared acts mainly as heat, absorbed by water in the skin.
Researchers propose that 810 nm light acts on cytochrome c oxidase, an enzyme in the mitochondria, linked to cell energy (ATP) and a brief burst of signalling molecules. Tsai and Hamblin, 2017
At far infrared wavelengths, the main absorber is water rather than that enzyme. Vatansever and Hamblin, 2012 The same review calls the mechanisms for any non-heating far infrared effects "hypothetical".
Our article on the 1064 nm face mask wavelength covers how deeper near-infrared may act.
Which is better for skin and wrinkles, near infrared or far infrared?
The light trials on wrinkles used red and near-infrared on the face, so that is where the skin evidence sits. Far infrared research has focused on whole-body warmth, circulation and pain rather than wrinkles.
In a sham-controlled, double-blinded, split-face trial, 76 people had 830 nm near-infrared, 633 nm red, both, or a sham on one side of the face. Lee, 2007 Sessions ran twice a week for 4 weeks, with follow-up at 3 months.
- Wrinkles: down by up to 36% from baseline in the active groups.
- Elasticity: up by as much as 19%, with more collagen in skin samples.
- Tolerance: no adverse effects reported.
When people weigh near infrared vs far infrared for the face, the useful distinction is light versus heat. Near-infrared and red reach the dermis, where collagen sits; far infrared warms the surface, and chronic skin heating can cause erythema ab igne, a heat-induced discolouration. ICNIRP, 2013
What does far infrared sauna research show for heart health and blood pressure?
This is where far infrared has its main body of research, and it comes from whole-body saunas used as a heat treatment. A 2009 review found "limited moderate evidence" for lowering blood pressure and for heart failure.
That review gathered 9 papers. Beever, 2009 In one randomised trial of 28 people, systolic blood pressure fell from 125 to 110 mm Hg in the sauna group. Its author noted small samples and no blinded controls.
The largest trial, WAON-CHF, gave 149 people in hospital with advanced heart failure weekday sessions in a 60°C far infrared sauna for 2 weeks; its main blood marker did not differ from usual care, while 6-minute walking distance rose by 44.9 m against 12.7 m. Tei, 2016
Mayo Clinic says there is "some proof that saunas may help" with high blood pressure, heart failure and other conditions, and that larger studies are needed. Mayo Clinic, 2024
These results belong to whole-body heat, often in hospital, which a panel or mask does not provide. Our red light therapy vs infrared sauna comparison sets the two side by side.
Do far infrared clothes, socks and wraps do anything?
Small studies have reported effects on soreness, pain and circulation, but the evidence is early. These textiles and plasters are powered by body heat rather than by a heater.
- Sleepwear: football players wore far infrared garments as sleepwear for 10 hours a night over 3 nights, and soreness was lower at 48 hours. Tsai and Hamblin, 2017
- Knee plaster: in knee osteoarthritis, a plaster worn 12 hours a day, 5 days a week for 4 weeks saw joint fluid fall from 80% to 40% of patients. Tsai and Hamblin, 2017
- Socks: a study in 55 people found a significant change on one of nine pain measures. Vatansever and Hamblin, 2012
In a randomised trial of 145 people on haemodialysis, a far infrared emitter placed over the arm fistula for 40 minutes was followed by fistula malfunction in 12.5% over a year, against 30.1% without it. Lin, 2007 This was hospital care, not a home wellness routine.
What settings did near and far infrared studies use?
The near-infrared skin trial used sessions twice a week for 4 weeks. The far infrared work used daily sauna heat or devices worn for hours.
| Study | Band | Where applied | Temperature | Time | Per week | Weeks |
|---|---|---|---|---|---|---|
| Lee, 2007 (76 people, sham) | 830 nm, 633 nm or both | LED on half the face | Not stated | Not stated | 2 | 4, plus 3 months follow-up |
| Miyata, 2008 (188 people) | Far infrared, whole body | Dry sauna | 60°C | 15 minutes, then 30 under a blanket | 5 | 2 |
| Sleepwear study | Far infrared fabric | Worn overnight | Body heat | 10 hours a night | 3 nights | Under 1 |
| Knee plaster study | Far infrared | Plaster on the knee | Body heat | 12 hours a day | 5 | 4 |
The sauna row is a 10-hospital trial. Miyata, 2008 Every study applied light or heat from outside the body.
Is near infrared or far infrared riskier for the eyes?
Near-infrared needs more care around the eyes, because it reaches the lens and gives no glare to make you blink or look away. Industrial heat cataract has been linked mainly to years of intense near and mid infrared exposure.
ICNIRP puts it this way: "The lack of visible stimulus results in loss of the aversion response." ICNIRP, 2013 Glass and steel workers exposed to intense infrared every day for 10 to 15 years developed lens opacities. ICNIRP, 2006 Far infrared mostly heats the front of the eye, and its share of lens heating is normally small.
- Panel: wear the supplied goggles every session, eyes closed, and never look into it.
- Mask: the shell has an eye opening with no diodes over the eyes; keep your eyes closed and do not stare into the light.
Our guide to red light therapy goggles explains why invisible near-infrared calls for eye protection.
Can infrared heat or light harm your skin?
Heat is the main skin risk: ICNIRP notes that skin held at 44°C takes several hours to be damaged, while at 70°C it takes less than a second. ICNIRP, infrared Near-infrared is dose dependent, with moderate doses and higher doses behaving differently.
ICNIRP adds that "the absence of pain is not an indication of lack of an adverse effect", and reports no cases of erythema ab igne from infrared cabin use. ICNIRP, 2006 Its cabin guidance advises stopping and seeking advice if reddening lasts more than a day. ICNIRP, warming cabins
For near-infrared, high doses can raise skin enzymes linked to photoageing, while low to moderate doses may be protective. Tsai and Hamblin, 2017 Skin above about 39°C also matters, so timed, moderate sessions make sense, as our article on how much red light therapy is too much explains.
Who should check with a doctor first:
- Sauna heat: caution in pregnancy, with multiple sclerosis, when unwell or trying to conceive. Cleveland Clinic, 2026
- Infrared cabins: advice first if you are at risk of overheating or have heart disease, and no use within 24 hours of intensive sun. ICNIRP, warming cabins
- Kivorla devices: our precautions rule out use during pregnancy, with epilepsy, a thyroid condition or thyroid medication, or over broken skin. The panel manual also lists breastfeeding, preparing for pregnancy, sunburn on the body in the past 2 weeks, seizures triggered by light and Fitzpatrick skin types V or VI.
Our precautions also rule out use with photosensitising medication, so anyone taking a medicine should check with their pharmacist or doctor before using the device.
Do Kivorla devices use near infrared or far infrared?
Both use near-infrared together with visible light; neither is a far infrared heater or sauna. They deliver light at the skin in timed sessions, while warmth stays mild.
The 4-Wavelength Red Light Therapy Mask is a cordless, full-face silicone shell with an eye opening. Its red mode combines 665 nm red with 850 nm and 1064 nm near-infrared; its blue mode combines 460 nm blue with 850 nm near-infrared. The 9-Spectrum Red Light Therapy Panel carries near-infrared at 810, 830, 850 and 1060 nm, plus 480, 590, 630, 660 and 670 nm, each dimmable from 1 to 100%. Its surface stays at or below 40°C.
- Mask settings: brightness 50, 70 or 90% and a 5, 10 or 15 minute timer, set on the handheld controller or by voice.
- Mask schedule: the manual allows 10-minute sessions up to 4 times a week at high brightness, or 15-minute sessions up to 3 times a week, never more than 20 minutes a day.
- Panel position: hang it on a door or wall with the included door hook and pulley, or stand it upright on the floor; about 6 inches for a joint, 12 for a broad area.
- Panel timing: 10 to 15 minutes per area, set on the controller, with at least 6 hours between 30-minute sessions.
- Near the face or neck: place the panel side-on, never aimed straight at the face, with goggles on and eyes closed.
- If skin feels hot or stays red: step back from 6 to 12 inches, dim the channels or shorten the timer, which starts at 1 minute.
- Sauna days: keep panel and mask sessions separate from sauna sessions, on cool, dry skin.
Read the precautions before ordering. Standard shipping to the US, UK and Germany is free. Under our return and refund policy, returns are accepted within 30 days: an unopened device with its seals intact is refunded less a 10% restocking fee, and an opened device that is undamaged and complete is refunded less 20%.
Kivorla devices are general wellness devices, not medical devices, and they are not heaters or saunas. Speak to a doctor before sauna or heat use if you have a heart condition, are pregnant or feel unwell, and see a doctor about any skin change that lasts.