How Long Do Batteries Last in Fairy Lights?

Whether you’re hanging battery fairy lights up for festive seasons or to set the mood in public places, fairy lights have an important place.

Fairy lights contribute to indoor and outdoor d├ęcor in public relaxation centers like bars and restaurants and set the mood in festive seasons.

When using battery fairy lights for any of these purposes, one might need to ascertain how long do batteries last in fairy lights.

As it’s important to prepare towards replacing the batteries as often as required so that the lights don’t go off unexpectedly.

how long do batteries last in fairy lights

What Batteries Do Fairy Lights Use?

Depending on the size of the led bulb, Fairy lights often use regular alkaline AA batteries and AAA batteries for power.

An AA battery has a standard volt of 1.5 with a capacity of about 2500 mAh and will effectively power fairy lights for several hours, for AAA batteries to deliver the same level of efficiency, you’ll need to determine the capacity of the led lighting on your fairy bulbs to decide how many will work to power it effectively.

How Long Do Batteries Last in Fairy Lights?

Depending on the quality of the led bulbs, fairy lights stay on for hours, when powered with quality batteries.

The light produced in fairy lights from AA and AAA batteries may differ in hours.

1. How long do AA batteries last in fairy lights?

AA batteries have a larger capacity than AAA batteries and may give between 12-40 hours of service time on your fairy lights, depending on the factors of use.

2. How long do 3 AAA batteries last in fairy lights?

If you’re using 3 AAA batteries on your fairy lights it would also serve you more than 12 hours of use, depending on the battery quality and length of your fairy light.

Factors That Influence How Long the Battery Operated Fairy String Light Will Last

1. Battery capacity

Fairy string lights powered by a high-capacity battery will usually hold more charge, and last longer than if powered by a lower capacity battery.

AA batteries have the capacity to hold more charge than normal AAA batteries of the same chemical composition, given that the fairy light draws current at the same rate.

For instance, if you have a 1m length fairy light you’re likely going to have up to 25 hours of power, however, an AAA battery of lesser battery capacity may not power your fairy lights for up to 10 hours.

Hence, look out for the capacity of the batteries you’re using on your fairy light, you’d often see the rating per hour written in milli-amperes or amperes.

This way, you can tell how much power your light will require and for how long, and decide the best battery capacity to choose for it.

2. Current consumption of lights

Fairy lights often have varying color compositions, with various energy consumption and brightness discharge.

This means some fairy string lights with the multi-colored light spectrum are likely to use up more current than fairy light with color temperatures within the orange and white light spectrum.

This means that, if the led bulbs on the fairy light use up about 50 mah and the string carries 10 of it, and another string fairy lights also have 10 bulbs, uses 25 mah per bulb for instance; a battery of 500 mah will last longer on the second string than on the first, due to its current composition.

When buying the pack of fairy lights, try to observe the specifications, composition of led bulbs, to determine how much current it would consume.

Lights with higher currents will not last as long as fairy string lights of the same capacity with the lesser current.

So how much current the fairy lights draw will determine how long the battery will last.

3. Length of the fairy lights

Ideally, fairy lights with longer lengths will draw more current than a shorter string with the same led bulbs.

Take curtain fairy lights for instance, they come in varying lengths, and will take up more power the longer it extends.

If the string has 10 led bulbs and another has 20 (which is often longer), and is being powered by the same battery capacity of 500 mah, for instance, you should expect longer use time on the first than the latter.

Another way to do this is to determine how many megawatts (mW) each bulb on the string uses, and determine how many watts per volt the battery delivers.

If the batteries deliver up to 850 watts per hour in total, and your bulb uses up to 50 watts for instance, then it means you should expect up to 17 hours on a single bulb, which will continue to reduce as the bulb increases.

Of course, you’d need more batteries, so the length of the string can be powered for longer hours.

Given a standard battery capacity, the light will only last as long as the battery can power the entire length of the fairy lights.

4. Quality of batteries

Certain brands use cheaper batteries on their fairy lights to cut down the cost of production and have the edge of their product being cheaper.

Others go for high-quality production regardless of the high costs.

The same goes for battery productions, in the case you have to change your batteries.

The quality of batteries that comes with your light or the one you purchase will generally determine the output of the batteries and how long they’ll last.

5. Service Time of fairy string light:

Your fairy light string batteries will last longer if you regulate how long the fairy lights stay on.

If you are conscious about switching them off when they’re not in use, you’ll have your batteries serving you longer than expected or influenced by the other factors above.

Generally, batteries with a smaller capacity may last longer if you keep them off on most occasions and put them on when the occasion demands than a high-capacity battery that’s often left working on most occasions.

What are the Best Batteries for Fairy Lights?

While there are various brands of batteries that can be used for fairy lights, Amazon basics batteries and Duracell batteries stands out as the best.

The batteries are designed to last up to 10 years of use and can be recharged continuously. The quality of these batteries makes a lot of difference in how long the fairy light batteries last.

How to Make Battery-Powered Fairy Lights Last Longer?

There are ways to make your fairy lights last longer when using batteries, of course, you don’t have the option of connecting it to a power source, here are certain things you can do.

1. Since you already know that certain led bulbs will consume more power on your batteries than others, it’s best to avoid them altogether if you need to have your batteries work longer.

2. Also, paying attention to the quality of batteries you included in the led lights you buy or the replacement you purchase will influence how well your batteries last.

The higher the quality of the battery, the higher the battery is likely to last.

3. Another hack to improve your battery power as discussed earlier is to only power them when you have to.

Since you’re not largely depending on fairy lights for visibility, it’s best to switch them on only when the occasion demands.

How to Fix Battery Fairy Lights?

There are several ways to fix fairy lights.

The first thing to do is to properly inspect the lights for faulty bulbs, or circuits.

If you notice that an entire length of the light isn’t working, the first bulb might be the reason.

It might have gone bad, or loosened from the circuit, inspect the bulb thoroughly to be sure, and you can take it out if need be.

That way, current can be supplied to other bulbs within the circuit.

You may also get a fairy light repair kit, which would include all the necessary guides that will help you fix a faulty battery fairy light.


1. How long do batteries last in led fairy lights?

Your batteries will last as long as the quality of your batteries, the output capacity, and the length of the fairy lights.

Some may last as long as 48 hours in total, while others may not last up to 12 hours, it all depends on a combination of different factors.

2. Is there rechargeable battery fairy lights?

Some AA and AAA batteries are designed to be rechargeable, so you may choose to go for them instead of the disposable type.

With the rechargeable batteries, you can extend the use life of your fairy lights than disposable batteries may afford.

3. Can I leave battery fairy lights on all night?

Yes, you may, but you shouldn’t.

Only if you have an all-night event that requires that you do. It’s best to switch them off when it is not necessary to leave them on so that you can preserve the battery life and prevent burning out of the led bulbs.

4. Can you cut battery fairy lights?

Yes, you can cut battery fairy lights.

Ensure it is not powered while cutting it if you feel the length is too long for its intended purpose.

5. How to calculate battery size for led string light?

Most manufacturers have the labels of the battery size and capacity on them.

When you purchase an LED light, it would also give you specifications on the battery size required, or you might just check the battery specification on the one that comes with it.

Generally, fairy lights with batteries only work with AA and AAA batteries, hence if you are on a DIY project, you may use a pair of AA batteries if you have up to 40 led bulbs.

6. How long do Duracell batteries last in fairy light?

Duracell batteries are efficient, but it still all depends on the other factors that have been listed above, but on average you may expect more than 40 hours of use before your next charge.