Red Light vs Near Infrared vs Blue Light: What Is the Difference?
Published October 2026. Updated October 2026.
Quick answer
Red, near infrared and blue are three positions on one scale of light, measured by wavelength in nanometers (nm). Blue is the shortest of the three, at roughly 450 to 495 nm, though AWA lists its blue modes at 415 nm. Red sits at roughly 620 to 750 nm and is visible. Near infrared starts just past it, runs to about 1,400 nm, and your eye cannot see it. None of them is "better." They are different wavelengths, and what you can compare on a spec sheet is which ones a device lists and how strong each is at a stated distance.
One scale, three neighbors
Light travels as a wave, and the distance between the peaks of that wave is its wavelength. We measure it in nanometers. Visible light spans roughly 380 to 750 nm, with violet at the short end and red at the long end. Blue sits near the short end, and red sits at the long end. Near infrared begins immediately after red and continues into a range your eye does not respond to.
Nothing switches on or off at the borders. "Red," "near infrared" and "blue" are labels for stretches of one continuous scale, and different sources draw the lines slightly differently. Read every range in this guide as approximate.
| Band | Approximate range | Can you see it? | Numbers on AWA spec sheets |
|---|---|---|---|
| Blue | About 450 to 495 nm (violet below that) | Yes, as blue | 415 nm on the face masks and the torch |
| Red | About 620 to 750 nm | Yes, as red | 630 nm on the masks, 660 nm on panels, belt and slippers |
| Near infrared | About 750 to 1,400 nm | No, not directly | 850 nm on every AWA LED device that lists it |
| Far infrared | Beyond about 1,400 nm | No | Heat from the sauna blankets and heating mat, not LEDs |
Band edges differ between standards and publications. Use this table as a map, not a rule.
Red light: the visible edge
Red light is the part you can see at the long end of the visible scale. Red LEDs in light therapy devices usually appear at 630 nm or 660 nm. They look red because the eye does respond to them, though less strongly than to other colors. On the standard daylight sensitivity curve, 630 nm registers at about 0.265 and 660 nm at about 0.061, relative to green light at 555 nm. That is why a 660 nm LED can look faint and still be putting out plenty of power. Brightness to the eye and power are two different things.
Near infrared: the part you cannot see
Near infrared starts where the eye stops responding. The numbers you will meet on device pages are 810, 850 and 940 nm. AWA devices list 850 nm. Because you cannot see it, you cannot tell by looking whether a near infrared LED is on. Some 850 nm LEDs show a dull red glow, but that is the very edge of their spread, not the near infrared itself. This is also why AWA guidance is to use eye protection as directed and not to judge by brightness. Our guide on eyes open or closed explains the routine.
Blue light: the short wavelength mode
Blue is the shortest wavelength of the three. In the textbook scale it spans roughly 450 to 495 nm, and wavelengths just below that look violet. The AWA face masks and the 3 in 1 torch list their blue mode at about 415 nm, which sits toward the violet end of what you can see. Blue is visible, so you can see when a blue mode is lit.
On the masks, blue is presented as its own mode that you select, separate from the red plus near infrared mode. The LX500 lists three modes: red plus near infrared, blue and mixed. The LX300 lists red, near infrared and blue. Follow the manual for how long to use each mode and for any extra eye directions. We make no claims about what any one mode does.
How AWA devices list each one
| Device | Wavelengths listed | Notes |
|---|---|---|
| FX300 and FX500 panels | 660 nm red and 850 nm near infrared | 60 LEDs on each, 30 at each wavelength. Irradiance is published by distance |
| LX300 and LX500 masks | 630 nm red, 850 nm near infrared, 415 nm blue | Modes are selected on the mask. LX500 lists red plus near infrared, blue and mixed |
| Vibrating belt | 660 nm red and 850 nm near infrared | 105 LEDs in a 3 to 2 ratio, plus a vibration setting |
| 3 in 1 torch | About 660 nm, 850 nm and 415 nm | A pocket size handheld with three modes |
| Sauna blankets and heating mat | Far infrared heat | Warmth products with temperature and timer settings, not LED light |
Equal LED counts do not mean equal output, because LEDs at different wavelengths can emit different amounts of power. A fair comparison starts from irradiance at a stated distance, not from counting chips. The FX300 lists 83.5 mW/cm² at 6 inches and the FX500 lists 94 mW/cm² at 6 inches. The irradiance specs guide has the full tables.
Why "which is better?" has no answer
Shoppers often ask whether red, near infrared or blue is best. As a statement about light, there is no ranking. They are different positions on a scale, and most home devices pair them: panels pair red with near infrared, and masks add blue as a separate mode. The useful questions are practical ones: which wavelengths the device lists, whether irradiance is given per wavelength or combined, at what distance it was measured, and what the manual says about session time and eye protection.
A fair comparison in five steps
- List the exact wavelengths each device states. "Red" and "660 nm" are not the same statement.
- Check whether irradiance is given per wavelength or combined.
- Note the distance behind each figure.
- Convert to energy per session with the dose calculator, using J/cm² = mW/cm² x seconds / 1000.
- Read the manual for session time, distance and eye directions for each mode.
For example, a panel listing 50 mW/cm² for red and 50 mW/cm² for near infrared delivers 30 J/cm² of each over a 10 minute session (50 x 600 / 1000), or 60 J/cm² added together. A device listing one combined 50 mW/cm² looks the same on paper and delivers half as much. These are example numbers for arithmetic only.
Common mistakes
- Thinking of the three as separate products instead of three positions on one scale.
- Judging power by how bright the light looks. Red can look dim, near infrared is invisible, and neither tells you the output.
- Assuming a near infrared LED is off because you see nothing.
- Comparing a per wavelength irradiance figure with a combined one.
- Comparing numbers measured at different distances.
- Reading a wavelength list as a promise about outcomes. It describes the light only.
Regulatory note: select devices carry FDA 510(k) clearance for specific, limited uses; most are sold as general wellness products. The AWA face masks are cleared for the face only. Read each product page and label.
Before you use any light device: read the label, follow the device manual, and use eye protection as directed. Ask a doctor or other qualified professional first if you have a medical question, take medications, are pregnant, or have light sensitivity.
Related guides
- 660nm vs 850nm wavelength guide
- LED face mask wavelengths explained
- Red light therapy explained: wavelengths, sessions and devices
- What irradiance means on a spec sheet
- Eye protection and goggles guide
- Compare AWA devices
Device pages
Read the full page and label for each device before you use it: AWA FX300 panel, AWA FX500 panel, AWA LX500 face mask. You can also browse the panels, masks or all AWA red light therapy devices.
Frequently asked questions
What is the difference between red light, near infrared and blue light?
Wavelength. Blue is the shortest at roughly 450 to 495 nm, red is roughly 620 to 750 nm, and near infrared runs from about 750 to 1,400 nm and is invisible to the eye.
Can I see near infrared light?
Not directly. Some 850 nm LEDs show a faint red glow because their output spreads slightly into the visible range, but the near infrared itself is invisible.
Which wavelengths do AWA devices list?
The panels, belt and slippers list 660 nm and 850 nm. The masks list 630 nm red, 850 nm near infrared and 415 nm blue. The torch lists about 660, 850 and 415 nm.
Do the face masks use a different wavelength for the blue mode?
Yes. The LX300 and LX500 pages list red at 630 nm and near infrared at 850 nm, with the blue mode at 415 nm. Follow the manual for each mode.
Does a higher wavelength number mean a stronger device?
No. Wavelength is a position on the scale, not a power rating. Power is shown by irradiance in mW/cm² at a stated distance.
How we create this guide
AWA sells red light therapy devices. We write these guides to explain how devices work and how to choose and use one. This is general information, not medical advice. Read each product page and label. See our editorial standards.