Lux to Lumen Converter

Lumens measure total light output from a source (luminous flux), while lux measures how much light reaches a surface (illuminance). The relationship is: Lux = Lumens / Area (m²). A 1000 lumen bulb produces 1000 lux at 1m², but only 250 lux when spread over 4m². Think of lumens as the total water from a hose, and lux as water per square meter on the ground.

Multiply your target lux level by area (m²). For 500 lux in a 20m² office: 500 × 20 = 10,000 lumens needed. Standard lighting levels: 300-500 lux for offices, 500-1000 lux for retail, 750-1500 lux for detailed work, 50-100 lux for corridors. Our calculator includes these EN 12464-1 standards for quick reference.

EN 12464-1 and IES standards specify minimum illuminance: Corridors 100 lux, Living rooms 150 lux, Offices 500 lux, Retail 500-1000 lux, Classrooms 500 lux, Workshops 750 lux, Precision work 1000-1500 lux, Surgery/labs 2000+ lux. Our calculator shows which standards your lighting meets.

Divide lumens by area in square meters: Lux = Lumens ÷ Area. For example, a 3000 lumen fixture over a 6m² desk: 3000 ÷ 6 = 500 lux. For non-square meter areas, convert first: 1 ft² = 0.0929 m². The calculator handles unit conversions automatically.

Calculate total lumens needed (lux × area), then divide by bulb output. For 500 lux in 25m²: 12,500 lumens needed. With 1200 lumen LED bulbs: 12,500 ÷ 1200 ≈ 11 bulbs. Add 20-30% for light losses to fixtures and surfaces. Our calculator provides estimates for common bulb types.

Beam angle determines how concentrated light is. A narrow beam (15°) produces high lux in a small area - good for accent lighting. A wide beam (120°) spreads light over a larger area with lower lux - good for general illumination. Same lumens through different beam angles give very different lux readings at the surface.