Logo

MonoCalc

/

Color Temperature Converter

Converter

Mode:

Input

Auto-convert on change

Result

Enter a colour temperature value to see the conversion and light-source identification.

Common White Balance Presets

PresetKelvinMired
Tungsten / Incandescent3200 K313 Mired
Fluorescent4000 K250 Mired
Daylight5200 K192 Mired
Flash5500 K182 Mired
Cloudy / Overcast6000 K167 Mired
Shade7500 K133 Mired

Light Source Colour Temperature Reference

Candle / Flame

1,000–2,000 K

Incandescent / Tungsten

2,000–3,200 K

Halogen

3,000–3,400 K

Warm White LED / Fluorescent

3,400–4,500 K

Daylight / Direct Sun

4,500–5,700 K

Flash / Electronic Strobe

5,500–5,600 K

Overcast Sky

5,700–7,000 K

Open Shade

7,000–8,000 K

Clear Blue Sky

8,000–20,000 K

About This Tool

Color Temperature Converter – Kelvin, Mired, and White Balance

Colour temperature is one of the most practical concepts in photography, cinematography, and lighting design. It describes the hue of a light source by comparing it to the colour emitted by a theoretical black-body radiator heated to a given absolute temperature. This converter lets you switch between Kelvin (K) and Mired (micro reciprocal degree), identify the real-world light source associated with a value, and find the nearest camera white-balance preset — all in a single step.

What Is Kelvin in the Context of Light?

Kelvin measures the colour appearance of a light source on a scale that runs from warm orange-red at the low end to cool blue-white at the high end. Common reference points:

  • 1800–2000 K — candlelight, very warm amber glow
  • 2700–3200 K — incandescent and tungsten bulbs, the familiar warm light of older household lamps and studio tungsten fixtures
  • 4000 K — cool white fluorescent tubes, neutral office lighting
  • 5200–5500 K — direct noon sunlight and electronic flash, the standard for "daylight" colour in cameras and film stock
  • 6500 K — overcast sky, slightly blue-tinted
  • 7500 K — open shade under a clear blue sky, noticeably cool

Counterintuitively, higher Kelvin values produce cooler, bluer light while lower values produce warmer, more amber light. This is because the physics of thermal radiation means that hotter objects glow blue-white, while cooler objects glow orange-red.

What Is Mired?

Mired (pronounced "MY-red") stands for micro reciprocal degree and is calculated as Mired = 1,000,000 / K. The inverse relationship means that lower Kelvin values (warmer light) have higher Mired values, and higher Kelvin values (cooler light) have lower Mired values.

The Mired scale is widely used in photographic filter and gel systems because equal numerical differences in Mired represent perceptually equal shifts in colour appearance across the entire Kelvin range. A shift of 50 Mired looks the same to the human eye whether you are moving from 2000 K to 2083 K or from 6000 K to 6383 K. In the Kelvin scale, those intervals are very different in size, making gel selection inconsistent.

Kelvin to Mired Conversion Formula

The conversion is a simple reciprocal calculation:

  • Mired = 1,000,000 ÷ K
  • K = 1,000,000 ÷ Mired

Example: 5500 K = 1,000,000 ÷ 5500 = 181.82 Mired. Conversely, 181.82 Mired = 1,000,000 ÷ 181.82 = 5500 K.

Camera White Balance Presets

Most digital cameras offer fixed white-balance presets that correspond to standard Kelvin values:

  • Tungsten / Incandescent (~3200 K, ~313 Mired) — removes the orange cast from household and studio tungsten lighting.
  • Fluorescent (~4000 K, ~250 Mired) — compensates for the green tint of older fluorescent tubes.
  • Daylight (~5200 K, ~192 Mired) — calibrated for direct sunlight in the middle of the day.
  • Flash (~5500 K, ~182 Mired) — matches the colour output of most on-camera and studio strobes.
  • Cloudy (~6000 K, ~167 Mired) — warms up the slightly blue cast of overcast skies.
  • Shade (~7500 K, ~133 Mired) — corrects the strongly blue light in open shade under a clear sky.

Mired Shift and Photographic Gels

A Mired shift is the Mired difference between two colour temperatures. It tells you exactly which type and strength of correction gel to place over a light to match your target. The formula is:

Mired Shift = Mired(target) − Mired(source)

A positive shift (target is warmer / lower K) calls for a CTO (colour temperature orange) gel. A negative shift (target is cooler / higher K) calls for a CTB (colour temperature blue) gel. For example, converting a 5600 K daylight source to 3200 K tungsten requires a +131 Mired CTO gel.

Approximate Colour Swatch

This tool renders an approximate colour swatch for any entered Kelvin value using the Tanner Helland Planckian locus algorithm, which curve-fits the sRGB coordinates of a theoretical black body across the visible-light temperature range. The swatch is a visual guide only — actual perceived colour depends on your display calibration, ambient lighting, and the specific light source involved.

Practical Uses

The colour temperature converter is useful for:

  • Photographers converting Kelvin to Mired when selecting Lee or Rosco correction filters for their lenses.
  • Cinematographers calculating the gel needed to match practical tungsten fixtures with HMI daylight sources on a set.
  • Lighting designers specifying LED fixtures or mixing light sources of different colour temperatures in architectural installations.
  • Display calibration professionals checking whether a monitor's white point (typically 6500 K or D65) matches a particular printing standard.
  • Students and educators learning the relationship between Kelvin, Mired, and perceived light colour in optics or photography courses.

Accuracy and Limitations

All arithmetic uses JavaScript double-precision floating-point, which is accurate to approximately 15 significant digits — far beyond any practical need for colour-temperature work. The light-source identification uses broadly accepted Kelvin ranges; your specific bulb or fixture may differ slightly from the listed range. The colour swatch is an approximation of a perfect black-body radiator and will not match real-world sources exactly — use it as a directional guide rather than a precise colour reference.

Frequently Asked Questions

Is the Color Temperature Converter free?

Yes, Color Temperature Converter is totally free :)

Can I use the Color Temperature Converter offline?

Yes, you can install the webapp as PWA.

Is it safe to use Color Temperature Converter?

Yes, any data related to Color Temperature Converter only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

What is colour temperature and why is it measured in Kelvin?

Colour temperature describes the hue of a light source by comparing it to the colour emitted by a theoretical black-body radiator at a given absolute temperature. As temperature increases, the radiator moves from red through orange and yellow to white and finally bluish-white. Kelvin (K) is used because it is the SI unit of thermodynamic temperature and the underlying physics is directly tied to thermal radiation — higher Kelvin values produce cooler, bluer light while lower values produce warmer, more amber light.

How does this colour temperature converter work?

Enter a value in Kelvin or Mired and the tool converts between the two units using the reciprocal relationship: Mired = 1,000,000 / K and K = 1,000,000 / Mired. It also identifies the matching light-source type, the nearest camera white-balance preset, and renders an approximate colour swatch using the Tanner Helland Planckian locus algorithm.

What is a Mired and when would I use it?

Mired (micro reciprocal degree) equals 1,000,000 divided by the Kelvin value. The Mired scale is useful in photography and cinematography because equal Mired differences produce perceptually equal shifts in colour appearance regardless of where you are on the Kelvin scale. Photographic correction gels and lens filters are rated in Mired shift values (e.g. +131 Mired) rather than Kelvin differences.

What is the difference between a CTO and a CTB gel, and how does the Mired shift calculator help me choose one?

CTO (colour temperature orange) gels warm light by adding Mired — they convert cooler, bluer sources (high K) to warmer amber tones (low K). CTB (colour temperature blue) gels do the opposite. The Mired shift calculator computes the Mired difference between your source and target temperature; a positive shift means you need a CTO gel, a negative shift means you need a CTB gel of that magnitude.

Why does the colour swatch look approximate rather than exact?

The swatch uses a mathematical curve-fit (Tanner Helland algorithm) that approximates the chromaticity of a Planckian black-body radiator in the sRGB colour space. Real-world light sources deviate from a perfect black body, monitors vary in their colour profiles, and the human visual system adapts to ambient illumination — so the swatch is a visual guide, not a precise colour match.

What colour temperature should I set my camera to for indoor tungsten lighting?

Tungsten or incandescent bulbs typically emit at 2700–3200 K. Most cameras include a Tungsten white-balance preset calibrated to approximately 3200 K (about 313 Mired). Setting that preset removes the orange cast you would otherwise see when recording under incandescent light with an auto or daylight white balance.