Flexible Boning Knives

We’re pleased to report that you can’t go wrong with any of the knives in our lineup. All did a serviceable job of boning chicken breasts, trimming tenderloins, and removing the bones from cooked pork shoulder roasts. But a few factors made some models slightly easier and more enjoyable to use.

The first and most important characteristic: sharpness. Because the blade of a boning knife is comparatively light, thin, and narrow, it can’t use its heft to force food apart the way a chef’s knife can. Instead, it relies almost entirely on the sharpness of its edge—particularly at the tip—to slice or make incisions. Some blades were sharper than others, effortlessly stripping away silverskin or scoring the fat cap on raw pork shoulders. We preferred models that had narrow edge angles of 14 or 15 degrees; one knife with an 18-degree edge angle felt less keen. And we liked very thin blades—0.84 millimeters or thinner when measured halfway between the spine and the edge. Surprising as it may seem, even a difference of 0.1 millimeter can make a blade feel less sharp. We also liked blades that maintained their sharpness over time; some started off sharp but felt duller over the course of testing.

Flexibility was critical. Unlike a chef’s knife or paring knife, a flexible boning knife has a certain degree of give so that it can bend and maneuver around bones, cartilage, and joints. Although all the knives in our lineup were marketed as “flexible,” the level of flexibility varied from model to model. Some blades were more rigid—they couldn’t hug the breastbone of the chicken or the bone of the pork shoulder quite as closely, leaving more flesh behind. Others were a bit too flexible and thus harder to control; at times, these knives felt dangerously slippery. We preferred blades that had a moderate level of flexibility, allowing for nimble but precise cuts with little or no wasted meat.

Finally, we looked at handle design. We liked handles that were made of textured, rubbery materials; slicker handles made it harder to maintain our grip when dealing with wet or greasy meat. But testers had different opinions when it came to the size of the handles. While a few large-handed testers thought thick handles (3.5 inches in circumference) were easier to grip, most preferred handles that were relatively slim—about 2.75 inches in circumference. Unlike a chef’s knife, a boning knife is often held with your pointer finger on the spine for added control when directing the blade. In this context, a thicker handle can make for less dexterous maneuvering, and a slightly thinner handle can be an advantage, allowing users to switch their grip more readily. Ultimately, though, handle preferences were personal, depending on the size of the user’s hands and how they liked to hold the knife.

We still like our old favorite. Its blade arrived (and stayed) relatively sharp and had good flexibility, helping it perform all the tasks well. And its big, grippy plastic handle is especially comfortable for large-handed users. Priced at $26.95, it’s now our Best Buy, a solid entry-level option for home cooks who don’t plan on boning chicken breasts or trimming tenderloins regularly.

We found a knife we like even better, though. Our new winner is the Zwilling Pro 5.5" Flexible Boning Knife ($99.95). It has a slender handle that allows users to vary their grip more easily. But it was this model’s blade, one of the keenest in the lineup, that put it over the top. It was so sharp that flesh seemed to fall away at its touch, and it maintained its edge throughout testing. At 5.5 inches, its blade was the shortest in the lineup, but in practice, that shorter length turned out to be an advantage, as it afforded more control and precision. If you do a lot of butchering at home, this knife is a worthy investment that will make even the most finicky boning project seem effortless.