Watt to lumen equivalent

Notes

• **Buy lumens, not watts.** A watt is what the bulb *consumes*; a lumen is what it *emits*. The habit of shopping by wattage only worked while every bulb was a filament burning at the same efficiency. A 75W incandescent puts out about **1,100 lumens**, and any bulb of any technology hitting that number will look the same brightness.
• A CFL reaches 1,100 lumens on about **18.3 watts** because it produces roughly 60 lumens per watt against 14 for a filament. Compact fluorescent — takes a moment to reach full brightness.
• **Running cost is where the difference actually shows up.** At three hours a day and $0.17 per kWh, this bulb costs about **$3.41** a year against **$13.96** for the incandescent it replaces. Multiply by the number of sockets in the house before deciding it is a small number.
• Packet equivalence claims run a little optimistic — a box marked "60W equivalent" is often 750–800 lumens rather than a clean 800. Check the Lighting Facts panel on the back, which has to print the real figure.
• Brightness is only half the choice. Colour temperature decides whether the room feels warm or clinical, and it is independent of both the watts and the lumens on this page.