Headlamp brightness is measured in lumens, and bigger numbers sell lamps, but more is not always better on the trail. For camp chores like cooking, reading, and finding gear in your tent, a low setting of around ten to thirty lumens is plenty and saves battery. For walking a trail at night, most hikers find that a medium setting in the range of one to two hundred lumens gives a clear view of the path without blinding them to the dark beyond it.

Very high settings, several hundred lumens and above, are useful for route-finding, spotting trail markers at a distance, or scanning a river crossing, but they drain batteries fast and are rarely needed for long. A lamp that offers several brightness levels is far more useful than one with a single blazing mode, because you will spend most of your time on low or medium and only switch up for short bursts.

Headlamps range from featherlight models barely heavier than a few coins to chunky lamps built for caving or mountaineering. For backpacking, a lamp in the lighter half of the range is usually the right call, since you wear it on your head for hours and notice every extra gram. Heavy lamps also tend to slip down your forehead as you walk, which is annoying on a night hike.

Weight is closely tied to battery type. Lamps powered by small rechargeable cells are often lighter than those using standard disposable batteries, but they need a charging plan. Lamps using common disposable batteries are easy to resupply in any town, but the batteries themselves add weight and waste. Think about your trip length: for a weekend, a rechargeable lamp is simple; for a week or more without power, disposable batteries or a small power bank may be more practical.

Manufacturers quote battery life at the lowest setting, which can be misleading. A lamp rated for a hundred hours on low might last only a few hours on high, so check the runtime at the brightness you will actually use. For most backpackers, the realistic need is a few hours of evening camp use per day plus occasional night walking, so a lamp that runs several nights on medium is a comfortable margin.

Carry a backup plan, not just a backup lamp. A spare set of batteries or a small power bank covers a dead lamp, a cold night that saps battery performance, or a longer-than-planned night hike. In cold weather, keep batteries warm in a pocket or sleeping bag, since cold reduces their output noticeably. Rechargeable lamps can usually be topped up from the same power bank you use for your phone, which simplifies your charging kit.

A red-light mode is one of the most useful extras. Red light preserves your night vision and disturbs campmates far less than white light when you are moving around the tent at night. It is also handy for stargazing and for reading a map without ruining your eyes adaptation to the dark. Look for a lamp where red mode is easy to switch on directly, not buried behind five clicks of white light.

Other features to weigh include a lockout mode that stops the lamp switching on inside your pack and draining the battery, a tilting head so you can aim light at your feet or a book, and some water resistance for rain. A comfortable, adjustable headband matters too, especially if you wear the lamp over a beanie in cold weather. Skip gimmicks like gesture controls unless you have tried them and genuinely like them.

For most three-season backpackers, the sweet spot is a lightweight rechargeable lamp with a red mode, several brightness levels up to a few hundred lumens, and a lockout feature. Test it on a local evening walk before a big trip: walk a dark path, cook a meal by its light, and see how the headband feels after an hour. The best headlamp is not the brightest one on the shelf, but the one you forget you are wearing while it quietly does its job.