Halogen 500 W: switching to LED without getting it wrong

First, find the cap engraved on the socket: R7s, E27, E14, G9 or G4. That decides everything. A 500 W halogen is replaced by an LED of around fifty watts, but if the socket is a linear R7s tube, a common format at this power, no screw-in bulb will fit.

What is the LED equivalent of a 500 W halogen bulb?

Count roughly ten times less stated power: 500 W of halogen is replaced by an LED of 45 to 55 W. The equivalence that matters, however, is read in lumens on the packaging, and it depends first on the cap of your socket.

In a living room, the issue is not the number but the rendering. A halogen heats up, yellows at the end of its life and consumes a lot for the light it gives. On a living room and living area renovation, switching the sources to LED often goes hand in hand with rethinking the lighting points.

Why wattage no longer tells you anything

The watt measures the energy absorbed, the lumen measures the light produced. A halogen gives back about 15 lumens per watt, an LED gives five to seven times more.

• Lumens: the only value comparable between two technologies
• Kelvin: the tint, from warm white to cool white
• Watts: a consumption, never a quantity of light
• Maximum power: the ceiling engraved on the socket, not to be exceeded

For a living area, the question often comes down to choosing the bulb power for a living room according to the surface and the real use.

Identify your cap before looking for an equivalence

The cap is moulded on the socket or engraved on the collar. Note the letter and the number, without relying on the diameter of the bulb in place.

• E27: large screw thread, the most widespread
• E14: small screw thread, compact light fittings
• G9 and G4: pins, common on wall lights and spots
• R7s: linear tube, the format of powerful halogen floodlights

If in doubt, the guide to identifying your bulb cap details the measurements. Once the reference is noted, the LED bulbs collection brings together 266 references as of 29 September 2026. On a sample of 33 of these listings, the declared caps are E27 at 42%, G9 at 27%, G4 at 24% and E14 at 15%: four credible replacement routes, and nothing for an R7s tube.

Is it possible to replace a halogen bulb with an LED bulb?

Yes, provided an LED model exists in your cap. Replacement is direct on E27, E14, G9 and G4 sockets. The blockage comes from the linear R7s tube: there, it is the whole light fitting that needs rethinking.

The simple case: the socket is E27 or E14

Unscrew, screw back, keep the light fitting. Just check that the LED power stays below the engraved maximum, and that the bulb fits under the shade. The details of the steps are here: switching from halogen to LED.

The case that blocks: the linear R7s format

The R7s tube slides between two spring sockets, at each end. No screw-in bulb adapts to it, and direct replacements remain rare and bulky. The honest solution is to change the support rather than force the source.

Converting a halogen floor lamp to LED

On a 300 or 500 W halogen floor lamp, the heat wears out the socket and hardens the wiring. Two routes open up: replace the source if the cap is standard, or move to an LED floor lamp that already integrates the source and the reflector. Before any handling, cut the circuit and let it cool: changing a halogen bulb without breaking it avoids leaving shards in the socket.

When no bulb fits, it is better to change the light fitting than to bodge an adapter. A new light fitting takes over the function of the lighting point and blends with the rest of the room. If you are equipping several homes or a site, the professional space centralises requests and quantities.

Which LED should replace the halogen?

Choose in lumens and kelvins, not in watts. For a living area, aim for 2700 to 3000 K and the flux equivalent to the old bulb. The colour temperature decides the atmosphere, the flux decides the comfort, and the cap decides the feasibility.

Colour temperature changes the whole atmosphere

• 2700 K: the warm tint of halogen, ideal in a living room and a bedroom
• 3000 K: slightly crisper warm white, a good compromise in the kitchen
• 4000 K: neutral white, for a worktop or a desk
• Above 5000 K: cool white, to be reserved for outdoors and garages

How many lumens per m² depending on the room?

Common practice uses a range per type of room, to be adjusted according to ceiling height and wall colour.

The full calculation is done room by room, in lumens per m², before choosing an LED light fitting.

Is it possible to replace a halogen bulb with an LED on a dimmer?

Yes, if the bulb is stated as dimmable and if the dimmer tolerates the low load of an LED. An ordinary LED bulb on a dimmer lights badly, buzzes or flickers. If in doubt, replace the source before suspecting the dimmer.

Replacing a pencil halogen bulb with a dimmable LED

The halogen pencil gets very hot and behaves well when dimmed. Its LED equivalent must carry the dimmable mention, otherwise the dimming becomes jerky. The dimmable LED bulb collection groups the models designed for this operation.

Why an LED flickers on an older-generation dimmer

An old dimmer is designed to consume several tens of watts. With the few watts of an LED, it drops below its triggering threshold and the light wavers. Understanding the older-generation dimmer helps to decide between keeping the switch and replacing it. If the hesitation persists between replacing the bulb and replacing the light fitting, describe your installation to us: our team will answer, and you can write to us with two photos of the socket.

What problems come with replacing halogen bulbs with LEDs?

Three disappointments keep coming back: a light that is too cool or too weak, a flicker on a dimmer, and a bulb that refuses to fit under the shade. None is fatal, all are settled at the time of choice, by reading the kelvins, the lumens and the dimensions.

The three classic disappointments

• The colour: a 4000 K bought by default cools an entire bedroom
• The flux: a 6 W LED does not replace a 100 W halogen
• The volume: a large heat sink gets stuck under a small shade

What are the drawbacks of LED lamps?

The LED loses a little brightness over time, dislikes poorly evacuated heat and depends on an electronic driver, sometimes sensitive to micro-outages. In exchange, it consumes five to seven times less, heats very little and dims easily. For a central point, an LED ceiling light settles source and support in one go, and a floor lamp covers the evening extra without drawing a new line.