The Best Bread Knife for Sourdough

This guide contains affiliate links. If you buy through them, I may earn a commission at no extra cost to you. Learn more

Sourdough is hard on bread knives. The crust is thick and crackly, the crumb underneath is open and soft, and a big boule can be wider than a lot of knives are long. A cheap 8-inch serrated knife from a block set will get through it, but it saws, tears the crumb and leaves a pile of crust shards on the board.

The good news: a proper sourdough knife doesn’t cost much. The three below cover budget, middle and upgrade. I picked them from manufacturer specs and from what bakers who slice a loaf every day report. I haven’t measured crumb loss with a ruler, and I won’t pretend I have.

The three picks

What makes a bread knife good for sourdough

Length. This is the big one. You want the blade to be longer than the loaf is wide, so you can make full strokes without the tip disappearing inside the bread. The Pantry Mama, a sourdough blog, recommends 10 inches for exactly that reason: you won’t run out of knife on wide boules and batards. Victorinox’s own guide to choosing a bread knife says 21 to 26 cm suits most kitchens, and that bigger loaves with harder crusts call for the longer end.

Serrations. The teeth do the work on the crust. They grip it and cut through before the blade reaches the soft center, which is why a serrated knife crushes less than a straight edge. Pointed serrations bite harder into a thick crust. Rounded “wavy” edges are a bit gentler and leave fewer crumbs on softer loaves. Both work on sourdough. Pointed teeth have an edge on very hard, dark crusts.

A stiff blade. A thin blade cuts easier, but if it flexes, your slices come out thick at one end and thin at the other. You want thin and stiff, not floppy.

A handle with knuckle room. On a flat board, a straight bread knife can catch your knuckles at the bottom of the cut. Wider blades help, because they put more height between the edge and your hand. So do offset bread knives, where the handle sits higher than the blade.

Weight. Lighter is easier to control for long, gentle strokes. Heavier can help on very hard crust. Most people do better with lighter.

Mercer Culinary Millennia 10-inch wavy edge: best budget

This is the knife you’ll see recommended over and over by home bakers, and the price explains a lot of it. At around $28 it costs less than a bag of good flour and a banneton. The Pantry Mama says she uses a Mercer 10-inch bread knife every day and calls out the single-piece high-carbon blade and the textured finger points on the handle.

Mercer calls this one the “wide” bread knife. The tall blade gives your knuckles more clearance than a narrow knife. The edge is wavy rather than pointed. Mercer describes the steel as high-carbon Japanese steel but doesn’t publish the hardness.

The handle is the same chunky Santoprene and polypropylene grip as the rest of the Millennia line. It’s comfortable for most hands and bulky for small ones. Mercer says not to put its knives in the dishwasher. A left-handed version exists, which matters with serrated knives, because most are sharpened on one side.

Get it if: you want a proven sourdough knife for very little money.

Victorinox Fibrox Pro 10.25-inch bread knife: lightest

Victorinox calls this its bread and pastry knife. It has a 10.25-inch (26 cm) wavy-edge blade and weighs just 4.8 oz, according to Victorinox. That’s light for a knife this long, which makes long, unhurried strokes easy. The Fibrox handle stays grippy even with flour on your hands, and Victorinox lists it as dishwasher safe.

It’s a little gentler on the crust than a pointed serration, so it shines on sandwich loaves, cakes and softer sourdough as much as on hard-crust boules. If you bake dark, blistered loaves with a really thick crust, the Tojiro below bites harder.

Get it if: you want a long, light bread knife that also handles cakes and tomatoes and can go in the dishwasher.

Tojiro bread slicer 270 mm (F-687): best upgrade

Tojiro is a Japanese maker known for its value gyutos, and this bread slicer is a quiet favorite with people who bake a lot. It has a 270 mm (10.75-inch) blade, the longest of the three, in molybdenum vanadium stainless steel at 60 HRC, according to Cutlery and More’s listing. That’s much harder than most bread knives, so the teeth should stay sharp longer. It weighs 6.1 oz and has a triple-riveted pakkawood handle.

At about $80 it costs more than the other two together. It’s also harder to find in US stores, and the wooden handle wants hand washing.

Get it if: you bake every week, slice big loaves and want a knife that feels like a real tool rather than a commercial utensil.

How to slice sourdough without crushing it

The knife is only half of it. Technique and timing matter just as much.

Wait for it to cool. This is the mistake almost everyone makes once. A hot loaf is still finishing inside, and the crumb is gummy. The Pantry Mama suggests 4 to 6 hours of cooling and says cutting too soon is the usual cause of sticky slices. If you need warm bread, reheat slices later.

Use long, light strokes. Victorinox says to use light pressure and long, even strokes instead of pushing down, because forcing the blade downward crushes the bread. Start at the far end of the knife, draw it back slowly over the full length, and let the teeth do the work.

Start through the crust at an angle. Get the teeth into the top crust with a few short strokes first. Once you’re through, switch to long strokes.

Turn the loaf for the base. The bottom crust is often the hardest part. If the knife struggles there, tip the loaf on its side and finish through the bottom crust from the side.

Slice on a wooden board. Victorinox notes that glass, stone and ceramic boards dull an edge faster. A big end-grain or edge-grain board also catches crumbs.

Hold the loaf with a claw grip. Fingertips curled, knuckles toward the blade. With a long serrated knife, slips usually happen at the end of the stroke, not the start.

How long does a bread knife stay sharp?

Longer than a straight knife. The edge sits in the recesses between the teeth, and Victorinox notes that most of it stays protected from the board. Many home bakers use the same bread knife for years without sharpening it.

When it does start tearing instead of cutting, you have a few options:

• An electric sharpener with a serrated setting. The Chef’sChoice Trizor XV sharpens serrated knives in its last stage, about 5 to 10 pairs of pulls according to the manual. My Chef’sChoice guide covers it.
• A tapered rod. You can sharpen each serration one by one with a thin ceramic or diamond rod. It works, but it’s slow.
• A professional. Victorinox recommends professional sharpening for serrated knives because each scallop has to be done individually.
• Replacement. With a $28 Mercer, buying a new one after a few years is a reasonable choice.

Don’t put a serrated knife on a flat whetstone. You’ll grind the tips of the teeth flat.

Other jobs for a bread knife

A long serrated knife isn’t only for bread. Once you have one, you’ll reach for it for:

• Tomatoes, where the teeth break the skin without squashing the fruit
• Layer cakes, to level the tops and split layers
• Citrus, to cut through the peel cleanly
• Sandwiches, especially tall ones with crusty bread
• Pineapple and melon, to get through the rind

Victorinox lists tomatoes, pastries, citrus and layered cakes among the jobs its bread knives handle.

Mistakes that make sourdough slices worse

Cutting a warm loaf. It’s tempting, but the crumb is still setting. Wait.

Pressing straight down. It flattens the crumb. Use long strokes.

Using a knife that’s too short. If the tip disappears into the loaf, you’ll tear the far side.

Slicing the whole loaf at once. Sourdough keeps much better whole. Cut what you need and store the loaf cut side down on the board or in a bread bag.

Wavy edge or pointed serrations?

Both work. Here’s how they differ in practice.

If your loaves are typical home sourdough with a golden to medium-dark crust, a wavy edge is fine. If you bake very dark, thick-crusted loaves, pointed serrations bite in more easily.

What about shorter bread knives?

An 8-inch bread knife works on small loaves, baguettes and sandwich bread. The rule is the same: the blade needs to be longer than the loaf is wide. For a typical 8 to 9-inch boule, that means 10 inches or more. If you only bake small batards, a shorter knife is fine.

Do you need a bread knife at all?

If you bake sourdough, yes. A sharp chef’s knife can slice through crust, but it tends to crush the crumb, and you’ll hold back on the crust to avoid chipping a thin Japanese edge. A bread knife is cheap insurance for both the loaf and your good knives.

My pick

For most home bakers, the Mercer Millennia 10-inch is the obvious start. It’s long enough for big boules, cheap and proven by people who slice sourdough daily. If you want lighter and dishwasher-safe, get the Victorinox. If you bake every week and want an upgrade, the Tojiro 270 mm is the one I’d save for.

Storing a bread knife

A 10-inch blade often doesn’t fit in a standard knife block slot. A magnetic strip works well, and so does a plastic blade guard in a drawer. Don’t toss a bread knife loose in a drawer: the teeth snag on other utensils and get bent, and the person reaching in gets cut.

Wash it by hand with the edge facing away from you, and dry it right away. Crumbs and flour stuck in the serrations can hold moisture against the steel.