LED light bulbs for E27, E14 and GU10 compared

Choosing a light bulb: room and mounting first, then product

Anyone looking for a light bulb usually faces an existing lamp. The lamp holder is fixed, and what remains open is brightness, colour temperature and whether a dimmer or an app is involved. This page follows exactly that order: room and job, then cap and mounting, then the data of the bulb. It is a source-based analysis by the editorial team. We evaluate manufacturer claims, listing texts and register data. We have not measured any of the bulbs mentioned, and there is no documented hands-on testing for any model.

A light bulb is rarely the whole solution. Whether a lamp serves as the main light in the living room or is only one of several sources depends on the luminaire. A chandelier with several lamp holders adds up the luminous flux, a single floor lamp does not. How much light a room needs by area and use is explained in the article How many lumens per room. For planning a whole room, the lighting calculator works out a lighting requirement from area and use. You will find more lamps and luminaires for living spaces in the home lighting category.

Mounting decides the selection before data sheets come into it. If the luminaire is enclosed, heat builds up, and a dimmer in the circuit limits the choice. If the luminaire hangs from a hard-wired connection, the conversion is, if in doubt, a job for a qualified electrician. Changing a bulb in an existing lamp holder is a different process, but the same applies here: switch the power off, let the bulb cool down, then swap it.

Identifying the lamp holder: E27, E14 or GU10

The cap decides whether a bulb fits at all. E27 is the screw thread with a diameter of 27 millimetres, common in pendant lights, floor lamps and table lamps. E14 is the narrow thread with 14 millimetres, typical for chandeliers, small table lamps and wall lights with candle bulbs. GU10 is a push-in cap with two pins, locked with a quarter turn and found mainly in ceiling spotlights and track lights. The three caps are not interchangeable.

A detailed comparison is provided by the guides E27 or E14 and GU10 or E27. Uncertainty often arises over the wattage on the luminaire's rating plate. It is an upper limit, not a target value, and an LED with a few watts stays far below it. More on this is in the article Wattage and LED lamp holder.

For GU10 there is a peculiarity: there are also low-voltage spotlights, which are built differently. Before buying, look into the empty lamp holder and check whether it is mains voltage. Then there is the installation depth: the Philips LED Classic GU10 ten-pack states 54 millimetres height according to the product page. So measure the depth of your recessed fitting before you order a ten-pack.

Lumens instead of watts, colour temperature and colour rendering

With incandescent bulbs, brightness could be read from the wattage, but not with LEDs any more. What counts is the luminous flux in lumens. As a guide: 806 lumens are regarded as a replacement for a 60-watt incandescent bulb, and 470 lumens for a 40-watt one. According to the manufacturer, the Philips LED Classic A60 E27 matt states 806 lumens at 7 watts for the current version, and the Lepro E14 candle bulb six-pack 470 lumens at 4.5 watts according to the listing. You will find finer intermediate steps in the lumens to watts chart.

If more light is to come from one lamp holder, there are bulbs of a different magnitude. According to the EU product register, the Philips LED Classic A60 E27 six-pack has 1521 lumens at 13 watts, and the 100 watts in the title are only the comparison value to the incandescent bulb and not a power consumption. If you buy by the title and expect a 100-watt load, you are calculating with the wrong power draw. Worked examples on running costs are in the article LED power consumption and costs.

Colour temperature is stated in kelvin and describes only the shade, not the brightness. For living spaces, warm white light at around 2700 kelvin is the usual guide. What the scale from warm white to daylight white means is explained in the article Colour temperature in kelvin. With adjustable white, watch the reference: the luminous flux of 1100 lumens for the Philips Hue White Ambiance A60 E27 2-pack applies at 4000 kelvin according to the manufacturer, and the figure is missing for other settings. The advertised range of 1000 to 20000 kelvin in the listing is no yardstick for everyday living.

The colour rendering index Ra describes how natural colours appear under a light source, with 100 as the maximum. According to the register, the Philips LED Classic GU10 ten-pack and the Lepro E14 candle bulb six-pack have a value of 80, the Osram Superstar Classic A 60 Filament DIM likewise Ra 80, and the WiZ Smart LED E27 Color and Tunable White Ra 90 according to the register. A value of 80 is the usual minimum for lamps in living spaces. Where colours are judged, for example when applying make-up or painting, a higher value is advantageous. For the red component (R9), the product pages give figures only occasionally, and for the Philips GU10 the register gives a value of zero.

Checking dimmability: listing text does not replace a data sheet

Dimmable is not the same as dimmable. The bulb must be designed for it, and the dimmer must suit the bulb. With a wall dimmer, the type (leading-edge or trailing-edge dimmer) and minimum load are decisive. According to the EU register, the Osram Superstar Classic A 60 Filament DIM is entered as dimmable, but no document states a list of checked dimmers or a minimum load. The listing advertises compatibility with standard dimmers, but that does not replace a manufacturer statement. If you have a dimmer, check its minimum load and type yourself.

An example of contradictory claims is the Lepro GU10 LED with 345 lumens 10-pack. The listing advertises dimmable light. In the product register there are two entries for the same model, one with No and one with Yes for dimmability. With a ten-pack it is worth clarifying this before buying, especially if the spotlights are on a dimmer. By contrast, the Philips LED Classic GU10 ten-pack is clear: according to the manufacturer and the register, it is not dimmable. The Philips LED Classic A60 E27 six-pack and the Lepro E14 candle bulb six-pack are also not intended for dimmer circuits.

If an LED flickers or glows despite a suitable bulb, the cause is often the circuit and not the light bulb. Causes and remedies are described in the article LED flickers. If you do not need to dim anyway, you can choose simple packs without a dimming function and save yourself the check.

Smart bulbs: with or without a bridge

Smart light bulbs are controlled not by a dimmer but wirelessly. There are two common ways to do this. First, Wi-Fi directly: according to the manufacturer, the Tapo L510E is a dimmable E27 Wi-Fi bulb without an additional hub, with app, schedules and Alexa and Google Assistant control. According to the listing, it works only with 2.4 gigahertz Wi-Fi. According to the manufacturer, the WiZ Smart LED E27 Color and Tunable White communicates over Wi-Fi in the 2.4 gigahertz band and via Bluetooth for the white variant, and no bridge is needed.

Second, Zigbee with a bridge: according to the manufacturer, the Philips Hue White Ambiance A60 E27 2-pack communicates via Bluetooth and Zigbee. Without a bridge, control via Bluetooth and the app is possible, but for voice assistants the manufacturer's page requires the bridge. How many bulbs such a system manages is covered in the article Hue Bridge and bulb limit. With many bulbs in the house, a central system can be clearer than individual Wi-Fi devices, while with few bulbs the direct solution is often enough.

One thing applies to all wireless bulbs: if the lamp holder is cut off from power at the wall switch, the app and automations cannot be reached. If you have guests or flatmates, plan an additional push switch or agree beforehand how the switch is used. Details are in the article Smart bulbs and light switches. The bulbs also draw power on standby, with more under Standby consumption of smart bulbs. A classic wall dimmer does not automatically suit a smart bulb, because the dimming runs in the bulb's electronics.

Reading the EPREL class correctly

Since the labelling changeover in September 2021, the EU scale for light sources runs from A to G, and the early plus classes no longer exist. The class follows from the luminous flux per watt, multiplied by a factor from Annex II of Regulation (EU) 2019/2015. For non-directional mains light sources the factor is 1.000, and for directional mains light sources such as GU10 reflectors 1.176. Class E starts at 110 lumens per watt, class D at 135, class F at 85.

The product pages show how narrow the limits are. The Osram Superstar Classic A 60 Filament DIM reaches 136.6 lumens per watt with 806 lumens at 5.9 watts and is thus only just above the limit for class D. The Philips Hue White Ambiance A60 E27 2-pack reaches 135.8 lumens per watt with 1100 lumens at 8.1 watts, likewise class D with a small margin. For the Philips LED Classic A60 E27 matt, a difference of one watt between the older and current version (8 compared with 7 watts at 806 lumens) is enough to jump from class F to E.

For GU10 spotlights, the factor is worth a look: the Philips LED Classic GU10 ten-pack reaches 77.2 lumens per watt with 355 lumens at 4.6 watts, and 90.8 with the factor 1.176, so class F. The Lepro GU10 LED with 345 lumens 10-pack also lands in class F with 345 lumens at 4.5 watts. Without the factor for directional light, both would be rated too low. You should not adopt old efficiency claims in the listing, as the EPREL product register is what counts.

Comparison of the lamps mentioned

The table summarises values that appear on the respective product pages. The entry 'no data' means that the page contains no reliable value for it. No ranking is implied, because the models serve different jobs. Manufacturer values and register values are marked in the sections above.

How to read it: two models with the same cap usually differ not in purpose but in brightness, dimmability and control. If you have a dimmer in the circuit, first look for a bulb with documented dimmability. If you do not, you do not need this feature. The current price is shown by the price widget on the respective product pages.

Before buying, check: luminaire, IP rating and health note

Three checkpoints cover most wrong purchases. First, the lamp holder including height and maximum power of the luminaire. Second, the control: a dimmer must suit the LED. Third, the environment: enclosed luminaires trap heat, and in the bathroom or outdoors the IP rating of the luminaire must suit. The IP code is regulated in BS EN 60529, and in the bathroom the zones under BS 7671 Section 701 apply. Notes on this are in the article IP rating in the bathroom. With a 230 V hard-wired connection, the conversion is, if in doubt, a job for a qualified electrician.

Warm white evening light can make a living space more pleasant, but it does not replace advice on sleep. Basic information on the connection between light and sleep is in the article Light and sleep. If you want to use light therapy, you should know that it does not replace medical treatment.

The page shows a selection, not a market overview. Where a manufacturer document for the specific model is missing, this is stated on the respective product page. There you will also find the sources and the date of the source data.