1. Which direction does your window face?

If unsure, point at the window with a compass app. Northern hemisphere assumed; reverse north and south if you are below the equator.

South — brightest, hours of direct sun East — direct morning sun, then bright indirect West — bright indirect until afternoon, then direct sun North — gentle indirect light all day, no direct sun Interior wall — no window in line of sight

2. How far is the plant from the window?

At the window (within 30cm) 1-2 metres back 3+ metres back, or in another room

3. Is the window covered?

Bare window — no curtain or blinds Sheer curtain (light passes through) Heavy blinds, frosted glass, or buildings outside blocking sun

4. What time of year are you measuring?

Indoor light can drop 30-50% in winter even at the same window.

Late spring through early autumn Late autumn through early spring

How the estimate works

We combine your window direction, distance, curtain, and season into a lookup that maps to one of four light tiers used in horticulture: direct sun (25,000+ lux), bright indirect (10,000-20,000 lux), medium indirect (5,000-10,000 lux), or low light (500-2,500 lux). Then we filter our plant database to species that thrive in that range.

For more accurate measurement, install a phone app like Lux Light Meter (iOS) or Lux Meter (Android) and hold the phone where the leaves will be at noon. See our houseplant light requirements guide for the full background on indoor light.