There is no single light level that fits every houseplant. Sun-loving plants, bright-indirect-light plants, and low-light-tolerant species have different needs, and both duration and distance from the window matter. Use the plant’s species requirements together with how it responds in that location.
Start with the species, not a universal rule
A succulent, fern, and snake plant do not use the same amount of light. Check reliable guidance for the species or cultivar and treat terms such as low or bright light as ranges rather than exact points.
Distance from a window changes usable light dramatically
A room may look bright to a person while a plant receives little usable energy several feet from the window. Moving it closer to a window can matter more than adding another hour of weak ambient light.
Watch growth, color, and direction
Long stretched stems, small new leaves, or strong leaning toward a window can signal insufficient light. Bleached, dry, or scorched patches after a sudden move can indicate excess light or too-fast acclimation.
Change exposure gradually
A plant accustomed to low light can scorch if moved directly into intense sun. Increase exposure gradually and judge the response over days or weeks rather than a few hours.