Now reads the camera's own illuminant estimate instead of guessing from a photo — steadier numbers, and no longer thrown off by the colour of whatever you point at.
Read the colour temperature of the light you are working in, in Kelvin and tint, straight from your iPhone's camera.
HOW IT MEASURES
The camera continuously estimates the colour of the light falling on a scene — that is how it decides white balance in the first place. This app reads that estimate directly, so the number reflects the LIGHT, not the colour of whatever happens to be in frame. Point it at a room and it reports the room's light; a wooden table no longer drags the reading warm.
WHAT YOU GET
• Kelvin and tint, updating live
• Light type identified: tungsten, halogen, fluorescent, LED, daylight, overcast
• Spectrum bar showing where the reading sits, candlelight to open shade
• Freeze to hold a reading while you compare two sources
• Mired display for filter maths, and the CTO/CTB gel that closes the gap between two sources
• White balance suggestions per camera system
• History with timestamps, so you can compare rooms and times
HONEST ABOUT THE LIMITS
This is a phone camera, not a spectrometer. It reports correlated colour temperature and tint, which is what matters for matching white balance and choosing gels — it does not measure spectral power distribution or CRI, and it will not separate two sources that share a colour temperature but differ in spectrum. Mixed lighting returns a blend, because that is genuinely what the camera sees. For critical colour work, treat it as a fast field reading rather than a lab instrument.
WHO USES IT
Photographers matching ambient light · videographers keeping colour consistent between setups · gaffers picking gels · lighting designers · anyone who wants to know why a room photographs orange
Available in 25 languages.
Thank you! Simple and useful is exactly what we aim for. 🙏
So daylight is 9700 Kelvin?
Old Blue Donkey
Amazing that daylight registers as 9700 K. No thanks!
Developer Response
Thanks for pointing this out. Color-temperature estimation from the camera can drift under mixed lighting; we're improving the white-balance calibration so daylight reads closer to ~5500–6500K. We appreciate the catch.
We refreshed how the app is presented so it's clearer what it does: it reads the light itself, not the surface you point at. Measurement is unchanged in this release.
Version 1.0.26
The developer, Kyu-Hee Jang, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
Identifiers
Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
Identifiers
Usage Data
Diagnostics
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Kyu-Hee Jang
Size
68.9 MB
Category
Photo & Video
Compatibility
Requires iOS 16.4 or later.
iPhone Requires iOS 16.4 or later.
iPad Requires iPadOS 16.4 or later.
Mac Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
