Kelvin: Color Temp Meter

Christian Vergara

In-app purchases

About this app

Kelvin reads your camera's white balance sensor to measure color temperature in real time — no gray cards, no guesswork.

Most "color temperature" apps just sample pixels from a photo. Kelvin taps directly into your device's auto white balance hardware for fast, accurate CCT readings from 2000K to 10000K.

▸ REAL SENSOR READINGS
Kelvin uses your camera's AWB (auto white balance) gains — the same data the sensor uses internally to correct color. This gives you a true hardware-level measurement, not a software estimate from a jpeg.

▸ PRO FEATURES
Unlock everything with a single purchase or annual subscription:

• Gel Calculator — enter your source and target color temperature, instantly get the right CTO or CTB gel. No more gel swatch books.
• Color History — log readings with timestamps. Compare light sources across locations or track how light changes through a shoot.
• White Balance Lock — freeze the sensor at a specific Kelvin value for consistent, repeatable measurements.

▸ BUILT FOR SET
Designed for gaffers, DPs, photographers, and anyone who works with light. Match practicals to your key light. Verify LED panel accuracy. Check window light before you rig. Kelvin gives you a real number without carrying a dedicated color meter.

▸ HOW IT WORKS
Point your camera at a light source. Kelvin reads the AWB metadata streaming from the sensor and converts it to a correlated color temperature (CCT) in Kelvin. No photo is taken, no image is saved — just a fast, continuous reading.

▸ ACCURACY
Readings depend on your device's camera hardware. Devices with MANUAL_POST_PROCESSING support provide the most accurate results via direct AWB gain access. All readings are estimates — use professional instruments where laboratory precision is required.

▸ PRIVACY
Kelvin collects no data. No analytics, no tracking, no network calls. Everything stays on your device.

What’s new

Measure the color temperature of any light source in real time using your phone's camera.

Features:
• Live Kelvin readout with instant color temperature display
• Gel filter calculator — find the right correction gel for any lighting setup
• Color history — save and compare past readings
• White balance lock for consistent measurements

Built for filmmakers, photographers, and lighting professionals.