G4 light bulbs

A G4 LED bulb is a miniature bulb with two pins spaced 4 mm apart, designed for fixtures where space is tight. Before ordering, measure the socket and read the voltage on the fixture label: that is what decides compatibility, not the name of the base.

What is a G4 LED bulb and what is this base for?

A G4 LED bulb is a miniature bulb with two pins, with a gap of 4 mm between the pins. It fits into compact fixtures: wall lights, recessed spotlights, illuminated furniture. The models in the collection have IP20 protection, reserved for dry rooms, and a G4 base.

A two-pin base for fixtures where space is tight

The G4 is the smallest of the common pin bases. On the white LED model, that gives 3.8 cm in height for 0.9 cm in diameter: enough to fit into a wall light, a recessed spotlight in a dry bathroom or a glazed cabinet. Two fine pins, a short socket, and a bulb you forget once it is in place. To see where this format sits among the other sockets, browse the other bases, G4 and G9 included.

G4 LED bulbs 12 V or 220 V: check the voltage before buying

The name of the base says nothing about the voltage. Read the label on the fixture, the one on the transformer, or the reference of the bulb you are removing. A very low voltage fixture runs with a transformer, a fixture connected to the mains does not have one. If the information is missing, compare with 12 volt bulbs before confirming your basket.

Which G4 LED bulb to choose?

The 2 W clear model relies on a crisp, discreet look; the 1.5 W white LED model diffuses a warm white 2700-3500 K in a format of 3.8 cm in height for 0.9 cm in diameter. Both share the G4 base and IP20 protection for dry rooms.

2 W clear G4 LED bulb: discretion in a small fixture

The clear glass of the 2 W clear G4 LED bulb by Ideal Lux lets the source show and does not tint the light: suited to a discreet wall light or a spotlight you do not want to see glowing with colour. Its 1 cm diameter fits into the tightest sockets. A useful choice when the bulb stays visible but should go unnoticed.

1.5 W white G4 LED bulb: warm light in a small format

The 1.5 W white G4 LED bulb by Lucide has a warm white 2700-3500 K and a metal body. It is the look you expect from a reading corner or a niche lit in the evening. Before deciding between the two, look at the full range in the LED bulb range.

Is it possible to replace a G4 halogen bulb with an LED bulb?

Yes, provided the base is identical and the voltage compatible. A 1.5 W G4 LED bulb takes the place of a G4 halogen in the same holder, without modifying the fixture. Check the voltage on the fixture label and the available space: 3.8 cm in height and 0.9 cm in diameter for the white LED model in the collection.

G4 halogen bulbs: what changes in everyday use

A halogen runs hot and does not like fingers on its glass; an LED runs cool and has no incandescent filament. In practice, you can touch the bulb without gloves, you do not burn yourself changing it just after switching off, and the fixture stays cool to the touch. The look, however, depends on the stated colour temperature, not on the technology alone.

G4 bulbs 10 W and 20 W: read the power and the flux before replacing

The watts of a halogen do not translate into LED watts. Look instead for the luminous flux in lumens on the packaging, and compare like with like. Four points to check before ordering: the fixture voltage, the stated power and flux, the dimensions of the socket, and compatibility with an old dimmer. For a very low voltage circuit, see low voltage LED bulbs.

G4, G9, GU4: how to recognise the base of your fixture?

Three similar names, three different contacts: the G4 and the G9 are pin bases, spaced 4 mm for one and 9 mm for the other; the GU4 is a variant with a keyway. Only the marking on the holder, or the pin of the old bulb, lets you decide.

The number in the name gives the gap between the pins

The rule is simple: the number after the G corresponds to the spacing in millimetres. A G4 does not fit into a G9 holder, and the reverse is also true. The GU4 adds a keyway that prevents fitting the bulb the wrong way round. To compare the families, go through all bulbs, all sockets.

G40 and G45 bulbs: not to be confused with G4

These references designate globe bulbs, not a pin base. The name looks similar, the product has nothing to do with it. Rely on the marking of the holder and, failing that, on the shape of the bulb removed. Models with wide pins can be found among the GU5 bulbs.

What type of bulb exists?

Bulbs are first distinguished by their base: screw (E27, E14), pegs (GU10), pins (G4, G9, GU5.3). Then come the technology, the colour temperature and the format. The G4 is the smallest of the common pin bases, reserved for fixtures where space is tight.

Screw, peg and pin bases: reading the letters

The E signals a screw thread, the GU a peg contact, the G bare pins. Once this classification is clear, the choice narrows quickly. If your fixture has more room, look instead at the E27 screw base or the 220 V LED bulbs.

Small LED bulbs: what the format changes

A compact base requires a short bulb. On the white LED model, the height of 3.8 cm and the diameter of 0.9 cm are the two dimensions to transfer to your socket before ordering. For another use, filament bulbs and white bulbs cover more decorative needs.

What lights whiter, cool white or warm white?

Cool white appears whiter and harder: its colour temperature is above 4000 K. Warm white, around 2700 to 3500 K like the white G4 LED model in the collection, leans towards yellow and wraps the room. For a living room or a bedroom in the evening, warm white is the most comfortable.

Warm white 2700 to 3500 K: for which rooms?

Below 3000 K, the light settles without straining the eye: dining corner, bedside, cabinet niche. The white LED model in the collection falls within this range. To equip the rest of the house in the same register, see bulbs for the living room and bulbs for the bedroom.

A more neutral light: when to look at 3000 K?

Around 3000 K, the look stays warm but less yellow, useful in a kitchen or a hallway. The step is subtle: compare 2700 K bulbs and 3000 K bulbs before fixing a tone for a whole room.

How to install a G4 bulb in a fixture?

Switch off the power and let the old bulb cool down. Remove it by pulling straight: its two pins are pushed into the holder. Present the new bulb with the pins aligned, push without forcing until contact, then restore the power and check that it lights up. A damaged holder is replaced, not bent.

Changing a G4 bulb without forcing the pins

The pins of the G4 are fine. Align them with the holes in the holder before pressing, never at an angle. If the bulb does not go all the way in, the socket may be too deep: then compare the stated height, 3.8 cm on the white LED model, with the actual space. If in doubt about the holder, the LED bulb range gives the formats by family.

Cleaning a small fixture and keeping good contact

A dry dusting is enough, with no product on the pins. Check from time to time that the bulb is properly seated: a loose contact causes flickering. The metal body of the white LED model can be wiped with a soft cloth. If you are looking for the fixtures that take this type of bulb, browse our selection of fixtures.

How to wire 3 bulbs in parallel?

Each bulb is connected to the same two wires, live and neutral. You go from the terminal of the first to the second, then from the second to the third, without ever breaking the circuit between two points. Switch off the power at the breaker and have the assembly checked by an electrician if in doubt.

Series or parallel: why parallel is chosen

In parallel, each bulb stays independent: if one blows, the others keep lighting and the voltage of each is not divided. This is the usual wiring for a group of spotlights. Tighten the connections in suitable terminals, never on bare wire.

12 volt bulbs: the role of the transformer

On a very low voltage circuit, a transformer supplies the whole. Check that it supports the load of the LEDs installed and that the wiring matches what it accepts. The details are read on its instructions. For this type of installation, compare with 12 volt bulbs and low voltage LED bulbs.

What budget to plan and what warranty for G4 bulbs?

G4 bulbs remain entry-level models, with a price that depends mainly on the technology and the format. All the bulbs in the collection are guaranteed for 2 years. Payment is secure, delivery is tracked and returns are possible, with the Designix customer service to check a base before ordering.

What makes the price of a G4 bulb vary

The technology, the format and the material of the body weigh more than the base itself. The price of the day is shown in the collection grid, product by product. If you vary the uses, a detour via dimmable LED bulbs avoids ordering twice.

Checking your base before ordering

Reread the fixture label, note the voltage and measure the socket. A G4 base accepts nothing else, and a format that is too tall will not fit. If in doubt, the Designix customer service answers before purchase. To see where this bulb sits in the whole catalogue, open the Designix lighting catalogue and all bulbs, all sockets.

Secure payment, tracked delivery, possible returns and Designix customer service: everything you need to order the right bulb first time.

Frequently asked questions about G4 bulbs