Luminous Intensity Converter

Convert luminous intensity (candela) for LED and lighting specifications

Luminous intensity is the measurement you see when a product spec lists a value in candela (cd) or millicandela (mcd). It describes how intense a light source appears in a specific direction. That direction part matters because many LEDs and lamps do not emit light evenly in all directions. Two products can have the same lumens but very different candela ratings if one is tightly focused and the other is wide and diffuse.

This converter is built for one practical job: translating luminous intensity units so you can compare datasheets and product listings consistently. If one LED is quoted as 18,000 mcd and another is quoted as 25 cd, you need a quick, reliable way to get them into the same unit before you decide which part is brighter in the relevant beam direction. This calculator converts between candela (cd), millicandela (mcd), kilocandela (kcd), megacandela (Mcd), and candlepower (cp).

To use it, enter the intensity value exactly as shown on the product sheet, choose the unit it is currently expressed in, and choose the unit you want to see. The primary result shows the converted value in your target unit. If you enable “Show the equivalent in all units,” the calculator also provides a compact reference list in every supported unit so you can copy and compare quickly across multiple listings.

Assumptions and how to use this calculator

• This converter only changes units for luminous intensity. It does not convert between lumens, lux, and candela.
• Metric prefixes are treated strictly: 1 cd = 1,000 mcd; 1 kcd = 1,000 cd; 1 Mcd = 1,000,000 cd.
• Candlepower (cp) is treated as equivalent to candela for practical comparison, which is how it is commonly used in modern product listings.
• Inputs can be estimates. If a spec is rounded, your output will be equally approximate.
• For extreme values, two-decimal rounding can hide small differences. Use the “all units” view to sanity-check scale and direction.

Common questions

What is candela and what does it actually tell me?

Candela is the SI unit of luminous intensity. It describes perceived light power emitted in a particular direction. In buying terms, it is most useful for comparing how “punchy” a beam is at its brightest point, especially for indicator LEDs, spotlights, and focused optics.

Is millicandela just candela divided by 1,000?

Yes. One candela equals one thousand millicandela. Many small LEDs are quoted in mcd because the values look cleaner at smaller scales. Converting to cd helps when you are comparing against stronger emitters or spotlight specs that use cd or kcd.

Why do some specs use kcd or even Mcd?

Those are just metric prefixes for large numbers. High-intensity beams such as powerful flashlights, automotive lights, and tight optical systems can reach tens of thousands of candela, which is easier to read as kcd. Mcd is less common in consumer listings but can appear in specialized contexts.

Can I use candela to estimate brightness at a distance?

Not directly in a reliable way without additional information. Candela is directional intensity, while what you experience on a surface is illuminance, usually measured in lux. Lux depends on distance and beam distribution. If your decision is about light on a surface, you need a lux calculation or a beam angle model, not just a unit conversion.

Does candlepower equal candela exactly?

Historically, candlepower had multiple definitions tied to reference sources. In modern product specs and casual usage, candlepower is typically treated as equivalent to candela for practical comparison. This converter follows that common practical convention so you can compare listings that mix the terms.