Replace an incandescent bulb by checking the fixture first

An incandescent bulb is familiar, but its replacement still needs to fit the socket, the fixture, and the way the room is used. Start with the old bulb and fixture markings. Then choose output, color appearance, and controls for the actual task.

Capture the old bulb’s useful details

Before removing the bulb, note the base, shape, fixture location, and control type. Photograph markings if they are difficult to read. A replacement that shares the same screw base may still be too large for a shade or unsuitable for an enclosed fixture.

Use bulb types and fixture compatibility for a fit-first path. Stop for damaged sockets, water exposure, uncertain voltage, or work beyond normal bulb replacement.

Compare light output, not a familiar watt number

When moving to LED, lumens are the direct rated-output comparison. Watts describe power use. A watt-equivalent label can be a helpful shorthand, but it does not say how much light will reach a desk, counter, or floor.

Consider shade direction, mounting height, and glare before increasing output. The lighting specifications guide explains how lumens, Kelvin, CRI, and beam spread answer different questions.

Choose color for the visible room

Color temperature should be compared with the other lamps that are on at the same time. Test one replacement in the room before changing an entire set. A light that seems right in a store can look mismatched once it shares a shade, wall color, and daylight with the existing fixtures.

The Kelvin color-temperature guide helps make that appearance decision without confusing it with brightness or color rendering.

Include the control in the decision

An existing dimmer, sensor, or smart control can change which replacement is suitable. “Dimmable” is not a universal compatibility promise. Confirm the exact bulb and control documentation, then test one bulb through the usual range before buying more.

Use LED dimming guidance if the replacement flickers, buzzes, or cannot reach a useful low level. Record the working model so later replacements do not restart the same trial.