Petzl Swift RL headlamp review: an innovative torch with a mind of its own

Petzl Swift RL: first impressions

The Petzl Swift RL is one of the best headlamps we've tested for trail runners. It's lightweight at just 102g/3.6oz, but gives out 550 lumens on max power for two hours. 

The maximum output is 900 lumens for 2–30 hours (but that is on Petzl’s Reactive Lighting mode, hence the RL in the name). Turn this mode on and suddenly the torch detects what brightness it thinks you need, which in some situations works perfectly, saving and prolonging your precious battery and allowing you to focus on your running, climbing or hiking without having to reach up and press a button. 

However, we found that running with other people who were wearing very bright headlamps reduced the lighting from ours when we really did still need to light up lumpy ground underfoot. Oncoming car headlights and even reflective roadsigns also confused it into dropping the light levels too, suddenly leaving you in the dark. 

This head torch is light, but the weight is all up front, which makes it seem a bit top heavy. Also, there’s no rear safety light unless you clip on a small additional light. However, the split headband at the back is the definitely the comfiest fit for those with ponytails.

Petzl Swift RL: on the trails

The main difference between this Petzl head torch and all the others on test is the Reactive Lighting mode, which – if it works for you – is absolutely fantastic for prolonging the battery life of an already efficient headlamp. 

We really like wearing this headlamp, first tested in Chamonix following the UTMB 2019 (Ultra Trail du Mont Blanc) courtesy of Petzl. Our fully charged Swift RLs saw our team of journalists through a whole night bobbing around this epic 100+ mile race via mini-bus, running and mountain biking. 

However, that was also when we realized that in Reactive Lighting (RL) mode, it dropped its light levels when other people using headlamps were nearby, and even dimmed suddenly on encountering the reflection of light from road signs, casting ankle-turning curbs into shadow. So possibly the best time to use the RL mode is when you’re running alone in the mountains. 

We prefer to use it on Standard Lighting mode so there are no surprises! That makes for a brilliantly comfy, long-lasting and bright head torch suitable for testing mountain terrain and rocky trails. We often reach for this head torch because of its comfort. And if you have a ponytail, the split headband wraps above and below it very nicely.