White Balance Color Temperature Kelvin Meter
A fantastic tool for professional photographers, light enthusiasts and gardeners
When we released world's first app for measuring color temperature of light more than 10 years ago, it became very popular. This is the modern version that is appreciated by thousands of professional photographers around the world. Get perfect white balance settings for your camera, measure LED lights, and match your flash lighting with ambient conditions using precise color temperature measurements in Kelvin.
Usages
Photography & Cinematography
Perfect for professional photographers and cinematographers who need accurate color temperature measurements for perfect white balance settings. Know exactly which white balance setting to use on your camera (tungsten, fluorescent, daylight, cloudy, shade) for stunning, color-accurate photos and videos.
Also tells you which flash gels to use on your camera flashes to match the surrounding light.
LED Lighting & Indoor Design
Match new LED lights with your existing lighting by measuring exact color temperatures. Perfect for home lighting enthusiasts, lighting designers, and professionals working with architectural or display lighting. Measure screens, TVs, and displays to ensure consistent white points (D65, D50) across your entire setup.
Plant Growing & Aquariums
Measure and optimize your plant grow lights for ideal growing conditions. Perfect for gardeners and aquarium hobbyists who want to ensure their lighting provides the right color temperature for healthy plant growth.
Understanding Color Temperature
Warm and Cool White Light
Color temperature is a characteristic of visible light that measures the hue of light from a light source. Color temperatures are measured in Kelvin (K). Low color temperatures (below 4000 K) are called warm colors or yellowish white, while high color temperatures (above 6000 K) are called cool colors or bluish white.
What is Color Temperature?
Technically, the color temperature is the temperature of an ideal black-body radiator that radiates light of a comparable hue to that of the light source. A black-body radiator is a theoretical object that absorbs all electromagnetic radiation and re-emits it based solely on its temperature, following Planck's law of radiation. As the temperature increases, the peak wavelength of emitted light shifts from red through orange, yellow, white, and finally to blue.
Color temperature values are always approximations because real light sources are not perfect black-body radiators. Incandescent bulbs come close to black-body behavior, but fluorescent lights, LEDs, and other modern light sources emit light through different physical processes (such as gas discharge or electroluminescence) that produce discontinuous or irregular spectral distributions. These sources may appear to have a certain color to the human eye, but their actual spectrum differs significantly from that of a black-body at any single temperature. Therefore, we use the concept of 'correlated color temperature' (CCT), which represents the temperature of the black-body radiator whose perceived color most closely matches the light source, even though the spectral compositions may be quite different.
There is No True Color Temperature Value
The above has an important practical implication: different color temperature meters may report different Kelvin values for the same non-black-body light source, such as an LED. Since these sources don't have a true black-body spectrum, there is no single 'correct' color temperature value—only approximations based on different measurement algorithms and matching criteria. Each meter may use slightly different methods to calculate the closest correlated color temperature, leading to variations in readings. In essence, a true color temperature value does not actually exist for sources like LEDs; only estimated CCT values that attempt to describe their perceived color in black-body temperature terms. This is one of the reasons why professional Kelvin light meters often differ by several hundred Kelvins.
Color Temperature in Photography
Color temperatures are of high interest in all types of color photography and cinematography. The human eye easily compensates for the color temperature of different light sources. Most cameras today have Automatic White Balance (AWB), which attempts to do the same. In some conditions this works well; in other conditions, the results are poor. Many photographers therefore prefer to manually set the white balance value on the camera to match the color temperature of the current scene. With this app, you can measure the color temperature before setting the white balance on your camera to achieve more accurate, professional results.
Key Features
🌡️ Real-Time Color Temperature in Kelvin
The current color temperature in degrees Kelvin is continuously updated in real-time and displayed with a clear visual gauge. Point your camera at a white surface illuminated by your target light, and get instant measurements. High accuracy out of the box on most devices, with advanced calibration support for enhanced precision.
☁️ White Balance Camera Recommendations
The app automatically recommends the optimal white balance setting for your camera based on the measured color temperature. Easily set your camera to tungsten, fluorescent, daylight, cloudy, shade, or a custom Kelvin value for perfectly balanced colors.
🔦 Flash Filter Recommendations
A unique and powerful feature: the app automatically calculates what CTO, CTB, Green, and Magenta flash gels/filters to put on your flash lights to match the ambient lighting conditions. Configure your flash color temperature and available filters, and the app will recommend the perfect combination for seamless lighting.
📏 Green-Magenta Tint Measurements (Duv)
Beyond just color temperature, the app measures the green-magenta tint (also known as Duv or Δuv measurement) of light sources. This feature helps you achieve more accurate color correction and understand the full color characteristics of your lighting.
💾 Save Measurements with Notes
Save any measurement with a single tap. The app automatically saves date, time, degrees Kelvin (before and after calibration), green-magenta tint, and recommended camera white balance setting. Optionally you can also add custom notes to each measurement for future reference. Perfect for keeping track of different lighting setups and locations.
🎯 Optional Calibration for Maximum Accuracy
While the app provides excellent accuracy on most devices without calibration, you can optionally calibrate it with known light sources for even better precision. Use LED modules with specified wavelengths, calibrated lamps, or other reference sources to fine-tune measurements for your specific device.
📐 Mired Shifts for Fine Color Correction
The app displays Mired values, which are convenient for quantifying the difference between two light sources' color temperatures. This is especially useful for photographers working with color correction filters and understanding the practical differences between lighting conditions.
Additional Features
💡 Illumination Meter
The app also has a built-in illumination meter that can be switched on for continuous updated Lux (lx), Foot-Candles (fc), or and Exposure Values (EV). For a full-featured Lux Meter with a light exposure calculator, please see our popular Lux Meter app.
⬛ Spot Metering & Adjustable Measurement Area
The app measures color temperature in a specific area of your camera preview, indicated by a rectangle. Adjust the size of the measurement area by dragging the arrows to focus on small surfaces or avoid shadows.
🔆 High Contrast Mode
Toggle high contrast mode for improved visibility in bright conditions or for users who prefer enhanced text and UI element contrast.
📅 Date and Time Formatting
Customize how dates and times are displayed throughout the app with support for multiple international formats including 12/24-hour time and various date notation styles.
How to Measure
How to Measure Color Temperature
To measure with the app, point your smartphone's camera at a white or gray surface - a white piece of paper works perfectly. Ensure the surface is only illuminated by the light source you want to measure, with no other light sources or color casts. If you want to measure a specific light source, it's crucial to eliminate surrounding light for accurate results.
How Accurate are the Measurements?
Accurate color temperature measurement is more complex than it might seem (see the section Understanding Color Temperature above. On phones and tablets, it's complicated further by the fact that all devices handle colors differently. Uncalibrated values from the app provide good accuracy on most devices. Using calibration with proper white surfaces evenly lit by reference light sources, you can achieve very good accuracy - often comparable to dedicated hardware meters at a fraction of the cost.
Tips for Maximum Accuracy
For best results: Use a pure white or gray surface without any color tint. Ensure only your target light source illuminates the surface. Avoid hand reflections that can tint the light. Fill as much of the camera preview with the white surface as possible. Point the camera at the surface, never directly at the light source. If measurements seem incorrect, check for these common issues or reset and recalibrate if needed.
What Users are Saying in Official Reviews
"Wow!
This app is unbelievable. I can't believe that someone was able to concept this for a phone. I shoot events with 3 cameras and white balance them all using this app. It's become a EDC for me. Bravo to the designer."
"Very nice app, just need pay little money but it's very worth it, make my TV looking so much better after doing calibration white D65"
"A Long Time Photographer's Opinion
I have either dabbled in or professionally worked in photography going on 40 years. I have never seen a color meter as accurate or easy to use as this app. I wish I could have used this back in the silver halide based years when it was much more difficult to get the results you needed post camera then it is now with digital based photography."
"Love it!
I'm the DP of a reality show on HBO and with our frenetic lighting and shooting, I needed a color temp meter that was fast and easy to use. I just downloaded this today and I'm looking forward to using this tool for my future shoots."
"Very accurate
I've found this to be a very accurate meter for color temperature, I tested against various light bulbs where I knew the exact color temp and it was spot on. I also appreciate the measurement of color tint, which was a big part of why I downloaded this app, I am looking at ways to incorporate that into my photo adjustments. The flash filter recommendations may also come in handy too."
"Incredible app!!! This is what I looking for in years!!!"
"Amazing App. As a working DP I use it all the time. plus it makes me look cool and technically prepared"
"Awesome
It's amazing how well this works, we compared to a colour meter and it stood up! Bravo"
"I just tested in my home with Auto WB versus the suggested temperature in K° of this app and the difference is quite visible. The picture taken with the suggested K° WB is much closer to reality than the one taken with Auto WB. I shoot in RAW, so I can always correct in post, but having the right WB while shooting is way better."
"Downloaded for fun, will use professionally
I initially downloaded this app so I could half-jokingly demonstrate to my sister why all the lighting in her house was horribly uneven temperature-wise. But I quickly saw immense value in it as a photographer due to it's accuracy and, most of all, a feature that recommends the appropriate gel to balance flashes with the the measured light source. 10/10, excellent app!"
"Very handy
Being able colour temperature with your phone is a game changer - you always have it with you."
"How wonderful! Finally, my digital images have their beautiful, true-to-life colors again, and the strange, bright Google colors are gone. Thanks!"
"Love it
Amazingly accurate! Within 5 as compared to a sekonic!"
"Super good! It measures temp and the mag/ver axis very accurately. What's missing is the amber blue axis, although I can quickly do it by eye. It saved me from buying a very expensive colorimeter. I paid for the monthly subscription, and it's worth it. All my photos now come out with many tones and exact colors. A dirt-cheap find. I highly recommend it."
"Amazing
I was about to purchase a Sekonic C-800 costing over a £1000, as I thought this app would just be too inaccurate for my needs. I was totally wrong. After I completed a few additional calibrations, this app performed amazing well and the accuracy was well within my limits. I therefore totally recommend you purchase this app if you're looking for an accurate, well thought out, and easy to use meter. Brilliant."
"All I can say is PERFECT!!! THANKS"
"Very useful app!
Totally recommended, filming in conditions of different color temperatures and being able to match it to your lamps and/or camera is very helpful to obtain an optimal result."
"Surprisingly accurate
As a theatre photographer I find this app extremely useful, and very accurate once calibrated. I tested it against a resident film crew's more elaborate and more expensive hand held colour meter and they were shocked to see how accurate this app is."
Need Help or Have Ideas?
We're committed to making this app the best it can be. Your feedback matters to us, and we personally respond to every user who contacts us. Whether you have questions, need support, or have ideas for new features, please reach out to us at [email protected]
Wide Language Support
The app has full support for 40 different languages, making measurement accessible worldwide.
Download the White Balance Kelvin Meter app now
Enjoy full functionality for a few weeks. After that, choose a one-time fee or subscription — still at a fraction of the cost of a dedicated color temperature meter device.