All LED globes emit some amount of blue light, but the amount varies significantly depending on colour temperature. Colour temperature is measured in Kelvin (K), and it describes the warmth or coolness of the light a globe produces. The lower the Kelvin rating, the warmer and more amber the light appears, and the less blue light it contains. The higher the Kelvin rating, the cooler and whiter the light, and the more blue light is present.
This is because blue light sits at the shorter wavelength end of the visible spectrum, around 380–500nm. Warmer colour temperatures naturally shift the spectral output away from these shorter wavelengths and toward the amber, orange, and red end of the spectrum.
We have had our globes independently spectrum-tested across our core colour temperatures. Here is a summary of the blue light ratios:
2000K (Extra Warm Amber): 1.3% blue light. Near-zero blue content. Ideal for relaxation and low-stimulation environments in the evening.
2200K (Extra Warm): 1.4–1.5% blue light. Near-zero blue content. Our warmest clear and frosted option, suitable for ambient and decorative lighting where minimal blue light is preferred.
2700K (Warm White): 2.0–2.5% blue light. Very low blue content. Our most popular colour temperature for general home use, offering a warm, inviting tone similar to traditional incandescent bulbs.
For reference, standard cool white LEDs rated at 4000K typically contain around 15% or more blue light, and daylight-rated LEDs at 5000K–6500K contain even higher levels. Dedicated blue-blocking bulbs on the market typically operate at around 1800K and are engineered to eliminate blue wavelengths entirely, reaching 0% in the 380–500nm band.
If you are specifically seeking the lowest possible blue light output for sleep or circadian rhythm purposes, our 2000K amber and 2200K extra warm globes are the best options in our range. These are available across most of our product lines, in E27, E14, and B22 fittings.
All spectral data is based on independent testing by Everfine Corporation.