Room Lighting (Lux) Calculator
Room size and target lux → total lumens and number of fittings, with sourced reference lux values.
Open the toolLED lighting calculators: lux, lumens, beam angle and more
Free interactive calculators for planning LED, home and car lighting: room lux and lumens, watts to lumens, color temperature (Kelvin), LED strip power supplies, beam angle, and battery runtime. They run entirely in your browser, only use the numbers you enter and show their formula, units, sources and limits.
Featured tool: Battery Runtime & Pack Size Calculator
Need to calculate how many hours your 12V battery can power LED light bars, camping setups, or portable lights? Use our Battery Runtime Calculator to calculate run hours and estimate battery pack size (Ah/Wh) with depth-of-discharge and inverter efficiency settings.
Open Battery Runtime CalculatorLumens to Watts Calculator
Lumens ↔ watts converter with energy efficiency comparison across LED, CFL and incandescent bulbs.
Open the toolLED Strip Power Supply & Wire Sizing Calculator
W per metre × length → power supply wattage, current, feed points, and anti-voltage-drop wire sizing.
Open the toolBeam Angle and Spot Size Calculator
Mounting height and beam angle → spot diameter, or the beam angle for a wanted spot size.
Open the toolBattery Runtime Calculator for LED Lights
Battery capacity and power draw → estimated runtime, with usable capacity and converter losses.
Open the toolLighting Color Temperature Guide & Calculator
Interactive 2700K–6500K Kelvin previewer with room recommendations for bedrooms, living rooms, kitchens and home offices.
Open the toolPortable Power Station & Home Backup Calculator
Running watts & backup hours → required battery capacity (Wh), surge headroom, and power station sizing.
Open the toolUPS & Home Backup Battery Runtime Calculator
Device watts + battery Wh or Ah → backup runtime, required capacity and a matching UPS or power station class.
Open the toolWhich calculator for which job
- Room Lighting (Lux) Calculator: Enter a room’s size and its use or a target lux level to get the total lumens needed (lumen method) and, optionally, how many light fittings that takes.
- Lumens to Watts Calculator: Convert lumens to watts or watts to lumens for LED, CFL, halogen and incandescent bulbs using stated luminous efficacy (lm/W), and compare energy efficiency.
- LED Strip Power Supply & Wire Sizing Calculator: Enter an LED strip’s watts, length, voltage and distance to calculate power supply wattage, current, feed points, and anti-voltage-drop wire size.
- Beam Angle and Spot Size Calculator: Enter the distance to a surface and a light’s beam angle to get the size of the lit spot, or the beam angle needed for a wanted spot size, plus centre lux from candela.
- Battery Runtime Calculator for LED Lights: Enter a battery’s capacity and voltage and the power draw of LED lights or car accessories to estimate how long the battery can run them.
- Lighting Color Temperature Guide & Calculator: Simulate lighting color temperatures from 2700K to 6500K with an interactive slider, visual preview, Kelvin scale guide, and room recommendations for bedrooms, offices, and living spaces.
- Portable Power Station & Home Backup Calculator: Enter household appliance or camping device wattages and desired runtime to calculate required battery capacity (Wh), surge headroom, and power station sizing.
- UPS & Home Backup Battery Runtime Calculator: Pick your household devices (router, cameras, fan, LED lights) or enter watts, add your UPS or battery capacity in Wh or Ah, and see how long it keeps them running.
Frequently asked questions
Are the lighting calculators on EyourLife free to use?
Yes. All interactive calculators run completely free in your web browser with no registration, email sign-up, or software installation required.
How accurate are the lighting and battery calculations?
The tools calculate strictly from standard physics and electrical formulas (such as the lumen method, inverse-square law, and P = V × I) using the numbers you enter and cited reference standards (such as EN 12464-1). They cannot measure physical lamps, rooms, or batteries.
Can I calculate battery runtime for 12V car accessories and camping lights?
Yes. The Battery Runtime Calculator lets you enter capacity in Ah, mAh, or Wh, select your nominal voltage (such as 12 V or 24 V), and account for depth of discharge and converter efficiency to estimate run hours and size battery packs.
Do these calculators work on mobile phones?
Yes. The calculators are responsive and execute client-side JavaScript directly in your browser on mobile phones, tablets, and desktop computers without sending your data to any backend server.