Review: Peanut Li Beard Trimmer

It's thankless work updating a classic. Change too much, and the loyalists stage an uprising. Don't change enough, you can't capture a new generation who now expect more, new, better, or maybe even just pointlessly different.

And make no mistake: Wahl's corded Peanut beard trimmer is a true modern classic. It remains one of my personal favorites, as well. Its reputation has been forged, in part, by its dogged particularity. The OG Peanut looks as goofy as a cartoon dog, short and bulbous, shaped and often textured like the actual shell of a peanut. It has just four guards, and they don't adjust. Though the trimmer seems shaped to the bowl of your palm, it's too short to rest there: It's an agile little trimmer, held only in your fingers. Its rotary motor buzzes like a hive of wasps.

But the corded Peanut's reputation among barbers is no joke. In the 33 years since its release, the Peanut has ascended to standby status among haircutters who prize its tanklike consistency and relentless, constant-power rotary motor. “Get a Wahl Peanut; they last forever” is like a barber's mantra, a koan for trimmers of men. Consecutive haircutters in South Philly told me nearly these exact words after I asked what trimmers they use and like.

Such loyalty is double-edged. Wahl has tried in the past to update to a cordless Peanut, but pros I talked to viewed these forays with suspicion. Not enough pep, they said. Too little battery life. Barbers don't necessarily need portable: They need durable. The corded Peanut is a known quantity, an Energizer Bunny of a thing.

This is a lot of backstory for a beard trimmer, I know. But this is what faces Wahl's newest update to the Peanut, released in January 2025. The Peanut Li is, as its name suggests, a cordless Peanut with a long-lasting lithium-ion battery. The Li is sleeker, self-consciously modernized, though still textured and shaped as an obvious homage to the original. It's also a handsome pale blue.

The Li is, in short, a spirited attempt to thread the needle between classic and new. Frankly, Wahl may have succeeded.

Something Old, Something New, Something Blue

First things first: The blades on the new Peanut and the OG Peanut are the same blade. This doesn't mean the blade hasn't changed. The makers of classic designs and even classic beers tend to update them without telling you, and Wahl is no exception. The corded Peanut's blade been subject to “continuous improvements,” company reps told us.

Guardless, each Peanut offers much the same shave: an OK one. The Peanut's errs on the side of comfort, and so its shave is worse than a foil but better than most trimmers. It's a half-day shave, let's say. But in a great number of shaves, I have also never been nicked by a Peanut.

The Li has a longer grip than the original but weighs the same, a mere 4 ounces. Its top shape is also pretty much the same: The guards for the corded black Peanut fit on the new cordless Peanut Li, and vice versa. Each Peanut offers the same no-nonsense assortment of four guards, from an eighth of an inch to a half inch—an almost stubborn devotion to simplicity.

The Li can charge both with USB-C, and a countertop Wahl charging station (not included). But what makes the Li great as a travel charger is its whippet-quick charge and long battery life, a weakness in the previous model of cordless. The Li's paperwork promises 110 minutes of life after a 20-minute charge, already admirable. But it outperformed this. I left the thing buzzing for two and a half hours before it finally gave up.

The Li, like the old corded classic, is run by a rotary motor, generally prized over magnetic motors for battery life and steady power. But maybe counterintuitively, the battery-powered Li is technically more powerful than the corded one. Or, at least, the Li has the ability to be more powerful, clocking in at a maximum of 7,000 rpm vs. the classic Peanut's steady 5,700.

This was borne out by the evidence when testing each trimmer on a horsehair broom, to approximate how each Peanut would fare with the thickest of beards. The old-school corded Peanut can clog a bit if you try to run it through a horsehair broom, or the human equivalent. But as for the new Li? It's a little plugger. The motor's higher rpm stepped up, and I never quite got the thing to bog down completely.

But to preserve battery life, Wahl engineers confirmed, the Li doesn't rev at full steam all of the time. When you turn the two Peanuts side by side, it's clear from pitch and vibration that the new Peanut Li revs lower than the corded by default, when it's not working too hard. The corded Peanut gave a peppier shave, with fewer hair pulls, when using both trimmers to shave and detail my neck.

Stepping up the juice only during tough jobs is, on the one hand, excellent engineering. On the other, this seems to lead to a slight tradeoff when merely mowing down light stubble.

Comme Ci, Comme Ça

The Peanut Li is clearly a more sophisticated device. It involves electronics and sensors and multiple means of charging. It debulks thick beards better than the old corded. It looks a little aerodynamic, somehow. It's a fashionable-seeming color of blue. A little light display on the front of the device indicates battery levels, so you'll know in advance before a charge is needed. The Li is also a little quieter than the cordless, by a few decibels.

But the appeal of the old corded Peanut, the thing that made it a classic, is precisely its lack of sophistication. This simplicity means the device has very few failure points. That's why it lasts. Sure, you've got to oil your blades consistently and replace them when they go dull. But otherwise, the Peanut will go on seemingly forever. Anecdotally, old corded Peanuts have lasted for a decade or more, even among barbers who use them a lot. The rotary motor seems to be built like the engine on an old Honda.

And so while the blade is the same and the motor is similar—a gentle little buzzer that won't nick your neck—the new Peanut Li asks to be considered among a different generation of modern beard trimmer.

And then you find yourself asking questions like, Why is it good to have only four guards, once we've abandoned the outright simplicity of the classic Peanut? Why can't we have edgers, extra guard lengths, microgradations of guard that allow for an expert fade? The only real answer seems to be: because it's a Peanut. And Peanuts are simple.

This seems like a missed opportunity. Sometimes, more is more. Wahl seems to be betting, instead, on its legacy branding. Maybe the company is also betting that the old Peanut lovers would like to keep this outward simplicity while accepting the complications of sensors and electronics under the hood.

Baby steps, I guess. Unlike the previous cordless Peanut, this new cordless Peanut Li is an actual upgrade to the raw capabilities of its forebear, and time will tell whether it's as durable as its predecessor. But in the meantime, if I'm heading for a hotel and I reach for a Peanut to take with me? It'll be the Li.