Quick answer: LED is the better choice for almost every use a halogen bulb covers. For the same brightness, an LED draws roughly 75–83% less power (a 43 W halogen gives about the same 800 lumens as a ~9 W LED), lasts about 7× longer (≈25,000 hours vs ≈3,600), and runs much cooler at the fixture. The main caveats are on the swap, not the bulb: a low-voltage transformer, an old dimmer, or a tight enclosed fitting can each misbehave with LED. The checklist further down shows how to avoid all three.
Remember when choosing light bulbs was a simple task? You'd only consider the shape and the watts before making a purchase. Now it's more complex, and you must weigh your options thoroughly. This article focuses on halogen and LED lights, which are lighting staples that suit different situations. Below you'll find how each one works, a side-by-side of the numbers, and the practical checks before you replace halogens with LEDs.
What is a halogen light vs. LED?
Halogen bulb
Halogen lights are the more advanced cousin of incandescent lights. A halogen gas inside the bulb lets the tungsten filament burn hotter than a standard incandescent filament can, which gives brighter, whiter light and a somewhat longer life. The price is heat: a halogen lamp gets very hot and radiates much of its energy as infrared rather than visible light.
In contrast, LEDs are semiconductor lights. They produce light directly when current passes through a diode, so they don't need gas or a filament to operate.
How does the LED work?
LED bulb
An LED has a diode with two electrodes (anode and cathode) that let current flow in only one direction. As electrons move across the semiconductor junction they release energy as light. A small driver inside the bulb converts mains power to the low, steady current the LED chip needs.
How does a halogen light work?
Halogen bulb
A halogen lamp heats a tungsten filament until it glows, the same basic principle as an incandescent bulb. More heat means more light, which is exactly why it is inefficient: the filament has to be extremely hot to make visible light, and most of the energy leaves as heat. The halogen gas simply recycles evaporated tungsten back onto the filament, so the bulb can run hotter and last longer without blackening the glass.
Halogen vs. LED at the same brightness
Watts measure power used, not brightness — lumens measure brightness. So the fair comparison is power at equal lumens. Using the standard brightness levels of the common household sizes, and the halogen wattages that met US efficiency rules (EISA) for each lumen band:
| Brightness | Old incandescent | Halogen (EISA-era) | Halogen efficacy | LED at ~90 lm/W | Power saved |
|---|---|---|---|---|---|
| 450 lm | 40 W | 29 W | 15.5 lm/W | ~5 W | ~83% |
| 800 lm | 60 W | 43 W | 18.6 lm/W | ~9 W | ~79% |
| 1,100 lm | 75 W | 53 W | 20.8 lm/W | ~12 W | ~77% |
| 1,600 lm | 100 W | 72 W | 22.2 lm/W | ~18 W | ~75% |
Halogen efficacy is lumens divided by watts. The LED column assumes a typical 90 lm/W; many LED bulbs are more efficient, so real savings are often higher. Older, non-EISA halogens draw more for the same light.
Efficacy is the number to watch. Halogens land in the 15–23 lm/W range shown above; a typical LED bulb is several times that. Check any specific bulb's lumens and watts on its box, or convert with our lumens to watts calculator and compare bulb types in the bulb comparison tool. For a deeper explanation of why wattage no longer tells you brightness, see LED watt equivalent.
Differences between LED and halogen lights
You've probably noticed LEDs are taking over the lighting industry. Here are the differences that show why.
Halogen vs. LED: brightness
Halogen bulbs give about 15 to 23 lumens per watt, which is bright enough for home and office use. LEDs deliver several times more light per watt, so you can get the same brightness — or more — from a much lower-wattage bulb. The table above shows the exact pairings; for example, an 800-lumen halogen uses about 43 W while an 800-lumen LED uses about 9 W.
Halogen vs. LED: energy efficiency and running cost
Because a halogen makes light by heating a filament, most of the power it draws leaves as heat, not visible light. That is why its lumens-per-watt figure is so low. LEDs make light directly, so the same lumens cost a fraction of the electricity.
Put that in money. Running one 800-lumen bulb for 3 hours a day (≈1,095 hours a year) at $0.16/kWh:
| Bulb | Power | Energy per year | Cost per year |
|---|---|---|---|
| Incandescent | 60 W | ~66 kWh | ~$10.50 |
| Halogen (EISA-era) | 43 W | ~47 kWh | ~$7.53 |
| LED | 9 W | ~10 kWh | ~$1.58 |
That is about $5.95 saved per bulb per year versus halogen, and it multiplies: a home with 20 halogen downlights burning 3 hours a day would save on the order of $119 a year at these assumptions. Your tariff and hours will differ, so plug your own numbers into the electricity cost calculator or the LED savings calculator.
Halogen vs. LED: total cost over the bulb's life
Halogens cost less to buy, but they burn out sooner and use more power. Over 25,000 hours — roughly one LED bulb's rated life — the same 800-lumen light costs:
| Halogen (43 W) | LED (9 W) | |
|---|---|---|
| Bulbs needed for 25,000 h | about 7 (at ~3,600 h each) | 1 |
| Electricity over 25,000 h | 1,075 kWh ≈ $172 | 225 kWh ≈ $36 |
Electricity only, at $0.16/kWh, before the purchase price of the bulbs — and the halogen also means about six extra replacement trips. Estimate when an LED pays for itself with the LED lifespan calculator.
Halogen vs. LED: color temperature and color rendering
A halogen lamp typically emits a warm white light of about 2,700–3,000 K with a very high color rendering index (CRI) — close to 100. LEDs come in a wide range of color temperatures, from about 1,800 K to 6,500 K.
If you want the halogen look, choose an LED marked 2700 K and a CRI of 90 or higher; that is what keeps skin tones, wood, fabrics and food looking the way they did under halogen. Cheap LEDs with a low CRI are the usual reason people say LED light "feels flat". Check any bulb's rating with the CRI calculator or the color temperature guide. If you like how halogen warms as it dims, "dim-to-warm" LEDs imitate that effect — see dim-to-warm LED lighting.
Halogen vs. LED: life expectancy
Good-quality halogen bulbs last up to about 3,600 hours. At four hours a day that is roughly two to three years. LEDs are typically rated for 25,000 hours or more, which at four hours a day is about 17 years. That long life is a real advantage in recessed lights and high ceilings where changing a bulb is a chore.
Halogen vs. LED: durability
Halogen bulbs have a thin glass envelope around a delicate tungsten filament, so vibration and power surges can damage them, and a hot halogen can shatter if it is splashed with cold water. Skin oil left on a halogen's glass can also create hot spots that shorten its life, which is why the bulbs are usually handled with a cloth. LEDs are solid-state, with no filament to break, so they cope far better with vibration and knocks.
Halogen vs. LED: heat, infrared and ultraviolet
Halogens run hot: the glass is very hot to touch and a large share of the energy is radiated forward as infrared, which is why a halogen spotlight can warm whatever it points at. Quartz halogen lamps can also emit some ultraviolet unless the glass is UV-filtered.
An LED's beam contains almost no infrared or ultraviolet, so it is gentler on fabrics, artwork and skin — which is why LEDs suit museums, displays and jewelry counters. Two points to keep honest, though: an LED is not heat-free. The chip and driver do warm up, but that heat is conducted backward into the base and heat sink instead of being radiated forward in the beam. That is why the lens of an LED bulb stays much cooler, while the base and fitting still need airflow (see the checklist below). The US Department of Energy's LED lighting facts page covers how LED products manage heat.
Halogen vs. LED: risk of burns and fire
Because a halogen's glass and beam are so hot, they raise the risk of burns and of igniting nearby combustible material, especially if the wrong wattage is used in a fixture. LED bulbs run at a fraction of the power and their glass or lens stays cooler, so they are safer in that respect.
Halogen vs. LED: warranty
LED bulbs commonly come with multi-year warranties, while halogen bulbs usually carry shorter terms or none. Check the packaging, since it varies by brand.
Halogen vs. LED: for reading and task lighting
Both work well. Halogen's high color rendering makes colors look natural, and a good LED with a CRI of 90 or more matches it while using far less power. LED bulbs are also naturally directional, so a reading lamp or spotlight points its light where you want it rather than spilling it all around, as a halogen filament does.
Halogen vs. LED: dimming
Both technologies can be dimmed, and halogens dim smoothly all the way down because they are simple resistive loads. LEDs can be less predictable: dimming depends on the bulb, the driver and the dimmer working together. Use bulbs marked "dimmable" with a dimmer that supports LED loads, and check the pairing with our dimmability checker.
LED vs. halogen vs. incandescent comparison table
| Feature | LED | Halogen | Incandescent |
|---|---|---|---|
| Efficacy (lumens per watt) | Typically 80–120+ | About 15–23 | About 15 |
| Rated life | About 15,000–50,000 hours | About 800–3,600 hours | About 750–1,000 hours |
| Heat in the beam | Very little infrared | Very hot; strong infrared | Hot; strong infrared |
| Ultraviolet | Negligible | Some, unless the glass is UV-filtered | Small |
| Color rendering (CRI) | 80–95+ depending on the bulb | About 100 | About 100 |
| Upfront price | Higher | Low | Lowest |
| Running cost | Lowest | High | Highest |
Ranges are typical figures for common household bulbs; check the datasheet for a specific product.
Switching from halogen to LED: five checks before you swap
The bulb rarely fails you; the fitting around it does. Before replacing halogens with LEDs, check:
- Voltage. Low-voltage halogens (usually 12 V MR16 and G4) run from a transformer. Choose an LED rated for the same voltage and current type (AC or DC) your transformer supplies. Mains halogens (GU10, GLS, R-shape) need a mains-voltage LED.
- Transformer minimum load. Many low-voltage transformers specify a minimum load. A 5 W LED can fall below what a transformer built for a 50 W halogen needs, causing flicker or no light at all. Check the transformer's stated minimum, and if needed replace it with an LED-compatible driver.
- Dimmers. Older dimmers designed for halogen loads often don't work smoothly with low-wattage LEDs. Choose "dimmable" LEDs and an LED-rated dimmer, and verify the pairing with the dimmability checker.
- Beam angle and size. Spotlights come in narrow to wide beams. Match the beam angle (for example 24° vs 36°) to the halogen you're replacing, or work out the coverage with the beam angle calculator.
- Heat and enclosure. LED electronics dislike trapped heat. In a sealed or fully enclosed fitting, use a bulb rated for it and leave the ventilation the fixture was designed with.
To plan a whole-house or whole-room swap in one go, try the LED upgrade planner and the room lighting calculator.
Which is better: halogen or LED?
LED bulb
LEDs are the better option for most uses. They use far less electricity for the same lumens, last several times longer, stay cooler at the beam and are available in nearly every base and beam type halogens use. The main downside is a higher upfront price, which the running-cost table above shows is repaid quickly.
Halogen still has a narrow case: a fitting you can't easily change (for example a specific transformer or dimmer you can't replace), or a situation where you need the exact smooth dimming curve and perfect color rendering of a filament and can't find an LED that matches. Even then, in many regions efficiency rules are steadily phasing halogen bulbs out, so check what is still sold locally.
Also note that LEDs are not 100% "green" — they contain electronics, so recycle them as e-waste rather than throwing them in general waste (see how to dispose of LED light bulbs). They don't contain the fragile filament or the hot halogen fill gas, and their small power draw is what makes them the lower-carbon option.
Frequently asked questions
Can I replace a halogen bulb with an LED?
Usually yes. Match the base (for example GU10, MR16 or E27) and the voltage, choose an LED with the same or higher lumens, and check the transformer and dimmer as described in the checklist above.
What LED wattage replaces a halogen bulb?
Wattage isn't the right comparison — match lumens. An LED needs far fewer watts for the same light; at a typical 90 lm/W, an 800-lumen halogen (43 W) is matched by an LED of about 9 W, and the table near the top gives the other common sizes. Read the lumen figure on the box, or use the lumens to watts calculator.
Do LEDs really save money compared to halogen?
Yes. In the example above, an 800-lumen LED costs about $1.58 a year to run at 3 hours a day and $0.16/kWh, versus about $7.53 for the equivalent halogen — roughly $5.95 saved per bulb per year, before counting fewer replacements.
Why does my LED flicker after replacing a halogen?
The most common causes are a dimmer that isn't LED-compatible or a transformer whose minimum load is higher than the LED draws. Try an LED-rated dimmer, a non-dimmable setup, or a compatible driver.
Is halogen light better quality than LED?
Halogen has excellent color rendering (CRI near 100) and a warm, dimmable glow, but a good LED with a CRI of 90+ at 2700 K looks very similar. Cheap LEDs with low CRI are what look worse.
Last words
Green energy LED
LED bulbs are energy-efficient and long-lasting, and they replace halogens in nearly every fitting. They use roughly three-quarters or more less power for the same lumens, give off far less infrared heat in the beam and last about seven times longer. Pick the right voltage, dimmer and beam angle, choose 2700 K with CRI 90+ if you want the halogen look, and use the calculators above to check the savings for your home.
Do you have more questions? Feel free to reach us and we'll be happy to help.
Sources and method: halogen wattages are the US EISA-era maximums for each brightness band (29, 43, 53 and 72 W for 450, 800, 1,100 and 1,600 lumens), with efficacy calculated as lumens divided by watts; heat management per the US Department of Energy's LED lighting facts. Running-cost and savings figures are worked examples using the stated assumptions ($0.16/kWh, 3 hours a day, 90 lm/W for the LED), not measured results.
Jack Shi
Founder & editor, LEDaskJack Shi builds and writes LEDask, an independent LED-lighting tools project operated by clooms. He designs the calculators, checks their formulas and reference values against published engineering data, and writes the guides across the site.
